I had set up hhe for 1.3 some weeks ago but didn't do anything just cuz I don't know what to come up with so that it'd make any sense.
I remember in like iwad e4 there was like a map or two, where I remember walking on barrels, moving pods in some water cave in order to reach some place by walking on them (edit: I mean finite heights is well noticeable in vanilla game)
about texture1 causing crashes:
Check if crispy heretic has a -merge parameter just like chocolate doom. It's like merging iwad and pwad with deutex, but on runtime.
I use -merge instead of -file when running vanilla doom wads. Try that, maybe it'd work for you