They definitely did intend - in that particular puzzle - for you to stack up three boxes that were inside a building to get to the first accessible step of a broken stairwell, and retrieve the purple key-card. Otherwise, there wouldn't have been voiceover content/etc up there....
And if they intended our solution, I think they might have installed "friction" into their physics engine
Arm Sim 1998 was ambitious - far too ambitious for its rushed-to-release-date.
My partner suggests fancier visual armour/clothes for further fluff options - and maybe a more distinctive "Istaria" design for biped gear.