Have R2-D2 hover across the lava pool via this platform and then activate the astromech panel at the other side to extend a bridge across the pool. Then, use the Force to assemble the pieces into a platform.
To get across the lava pool in the cave, first grapple up to the high rocky ledge and destroy the structure there, knocking its pieces into the lava. Have C-3PO activate the protocol panel to open the locked door to the cave. In the room where C-3PO joins up, use the Force on the switches to revolve the platforms, using them to cross the lava safely.
