How do I do jumps while grappling? I did it one time on lvl 2, but I dunnow how.
I went mostly by feel, so sorry in advance if this sounds confusing:
When you use the grappling hook, you'll pulled towards the target. Without releasing the grappling hook key, use the jump button when the timing is right.
And from what I observed, the timing depends on the stage. On lvl 2, the right timing seems to be around the red zone of the targets. On a specific target in the beginning of lvl 3, you need to grab the target when you are almost going past it, then hold right and jump (and it needs to be done pretty quickly). On the blocks, you need to grab as close to the top edge as possible, and jump when you're around 1~1.5 blocks away from them.
Also, slightly off-topic, but if you grab the edge of a safe/gold block and don't jump, you get a pretty big boost forward when you reach the block