oooook.... I'm finding myself in a deep cave where apparently the fishies swim through air. I can't swim and my bot can't swim, although it did manage a bit back. So I'm in a bit of a pickle. I can't get the bot back to the sub because I apparently need the jump jet, which is safely stowed in a locker on the sub...
I couldn't get back into the alien structure in the cave either, first, since the bot/suit won't jump anymore (???) but luckily my last save was from inside, so I restarted from there, went through a gate, went home the old fashion way to fabricate a new jump jet and some purple tablets because I apparently need more of those... Once home I find I left the materials for the tablets on the sub, too... *eyeroll*
It feels like I've come somewhat too far to start over so I guess I'll have to patch things up as well as I can
EDIT: And after going through the gate, swimming back to my base, getting the gear I needed, taking my Bunny (small sub) back to that island and esentially abandoning it there, going back through the gate and leaving the alien structure.... swimming worked again.