While you are quite right that using a complete, fully functional game engine is a good idea for most projects, you may be overlooking a few crucial points:
Btw, another very good adventure game engine/IDE is Inform7. You basically describe the scenes, objects and interactions in more or less plain english and it "compiles" it into a working text adventure. I must admit, it's not completly to my liking (quite challenging to do some standard stuff). Here's an experiment i cobbled together a few months ago:
"Wizard" by "Rene Schickbauer"
maximum score is 10;
Section 1 - The Farm
Kansas Prairie is a room. "You are in the middle of the Kansas Prairie
+. Nothing but grey skies and brown grass to see, expect for Uncle Hen
+ry's farm to the east."
Uncle Henry's Farm is east of Kansas Prairie. "The farm looks quite ol
+d. Three of the five buildings are already collapsing and the main ho
+use is badly in need of a new roof. Only the small shed north of you
+seems well maintained."
A plough is fixed in place in Uncle Henry's Farm. "A lonely plough re
+sts in the middle of the yard." The description is " It looks ancient
+ and rusty, and it probably hasn't been moved for ages, since rust st
+ains the ground around it."
Instead of taking the plough, say "I'm not a horse. This is far to hea
+vy to move for a human."
A shed is fixed in place in Uncle Henry's Farm. The description is "Th
+is shed serves as the entrance to the storm shelter."
A main house is fixed in place in Uncle Henry's Farm. The description
+is "This is the main house of the farm. As well serving as squalid li
+ving quarters, kitchen and moonshine distillery, it is also the hen h
+ouse. The roof is rather leaky, but on the plus side, Uncle Henry can
+ grow his psychedelic mushrooms in the attic."
A haystack is fixed in place in Uncle Henry's Farm. "At the west side
+of the yard, you see a small haystack." The description is "Rotten as
+ it may look, this hay will be the only source of food for Uncle Henr
+y's two horses this winter."
Instead of taking the haystack, say "Well, i heard of searching for a
+needle in a haystack. But taking the whole haystack with me seems kin
+d of pointless."
Instead of searching the haystack:
if the needle is in Smurg begin;
now the player has the needle;
say "Amazingly, you find a sharp needle in the haystack!";
award 10 points;
otherwise;
say "You spent hours riffling through the haystack. But you fi
+nd nothing else.";
end if;
Section 1 - Shed and Shelter
The Inside shed is north of Uncle Henry's Farm. "This is a very *small
+* shed. There is a door on the south and a ladder leading down to the
+ storm shelter."
The Storm shelter is a room. "This massively build storm shelter will
+survive any storm! The three meter thick walls of concrete and the ma
+ssive, sliding steel door make sure of that."
The shelter door is a locked door. The shelter door is down from the I
+nside shed and up from the Storm shelter. The description is "This is
+ a massive, sliding steel door. It is nearly twenty centimeters thick
+ and damn near unbreakable. There is a keyhole on the left side of th
+e door frame."
Report opening the shelter door:
if the player is in the Inside shed begin;
say "You pull with all your might. Slowly, the heavy steel doo
+r starts sliding silently into its doorframe." instead;
otherwise;
say "You press the red button labeled 'Open door' and the door
+ swishes open, just like the one on Kirk's bridge." instead;
end if;
Report closing the shelter door:
if the player is in the Inside shed begin;
say "You push on the door with all you got. Slowly, the heavy
+steel door starts closing until it shuts with a mighty bang." instead
+;
otherwise;
say "You press the green 'Close door' button and the door slam
+s shut in less than a second." instead;
end if;
Understand "lock [something]" as locking keylessly. Locking keylessly
+is an action applying to one thing.
Check locking keylessly:
if the noun is open, say "You must close [the noun] first." instea
+d;
if the noun is not a door, say "[The noun] is not something you ca
+n lock." instead;
if the noun is locked, say "[The noun] is already locked." instead
+;
if the player carries the needle and the player is in the Inside s
+hed, try locking the noun with the needle instead;
if the player is in the Inside shed, say "You can't lock the door
+from this side without some sort of key!" instead.
Carry out locking keylessly:
now the noun is locked.
Report locking keylessly:
if the player is in the Inside shed begin;
say "You fiddle with the needle in the key hole for a few minu
+tes. Then you give up, slam your steel capped boot into the door fram
+e and [the noun] locks with rather pleasing 'clonk'." instead;
otherwise if the player is in the Storm shelter;
say "You flip over the deadbolt on [the noun] and it locks wit
+h a satisfying 'clunck'.";
otherwise;
say "You lock [the noun].";
end if;
Understand "unlock [something]" as unlocking keylessly. Unlocking keyl
+essly is an action applying to one thing.
Check unlocking keylessly:
if the noun is not a door, say "[The noun] is not something you ca
+n lock." instead;
if the noun is unlocked, say "[The noun] is already unlocked." ins
+tead;
if the player does not carry the needle and the player is in the I
+nside shed, say "You can't unlock the door from this side without som
+e sort of key!" instead.
Carry out unlocking keylessly:
now the noun is unlocked.
Report unlocking keylessly:
if the player is in the Inside shed begin;
say "You fiddle with the needle in the key hole. After a few m
+inutes you manage to unlock [the noun]." instead;
otherwise if the player is in the Storm shelter;
say "You flip over the deadbolt to unlock [the noun].";
otherwise;
say "You unlock [the noun].";
end if;
Report unlocking:
if the player is in the Inside shed begin;
say "You fiddle with the needle in the key hole and unlock [th
+e noun]." instead;
end if;
Section 998 - Play area limitations
Instead of going nowhere:
if the player is in Kansas Prairie begin;
say "The Kansas Prairie is vast and stretches seemingly foreve
+r into the horizon. You don't want to get lost!";
otherwise if the player is in Uncle Henry's Farm;
say "Uncle Henry told you not to go there!";
otherwise;
say "You bump into an invisible wall.";
end if;
Section 999 - Hidden Objects
Smurg is a room.
A needle is in Smurg. It unlocks the shelter door. The description is
+"A sharp needle. It looks new."
Not everything in this (rather badly designed) example works as expected, it's quite a mess and some things i did are needlessly complicated. But hey, i am a Perl guy. Explaining something to a computer in plain english lacks style ;-)