The rave takes about 25-30 seconds total. Horizontal lasers come in around halfway through. Keep calm, don't jump around too much (only the very bottom laser can hit you if you don't jump), and you'll be fine.
I skipped the airtank for sister by having her climb up to the top of the flooded stage after they combine, barely standing on the ledge and casting a shadow large enough for ROBert to dash through the light and swim through the water.
I played through this and fell at the end. The next time I played, I went offscreen, slowly crept off, went forward for a bit, and then my game froze. Lesson learned.
Hah, Sorry about that! I'll take a look, see if I can sort that out. You could probably guess at this, but that's not a typical use case :)