I'm aware macros are against the rules(as they should be) however can I use a macro to do my splits?

Livesplit allows you to bind keys to split, you don't have to use macros. However, livesplit should also split automatically if you're using the load remover

I meant to reset my timer lol. It's my "-" key but I it as a macro on the side of my mouse to keep both hands in place.

Oh, that's fine yeah x)