There seems to be a bug with collecting the coloured gems. Keep picking them up on a run and when I return to the upgrade screen it says that I have zero
This is a decent little platformer which is completely ruined by the ridiculous ghost/snake thing at the end which can only by beaten through pure luck
A good place to farm is the middle square on the top row of the map. There are a load of bushes there which give lots of 10s and 20s so just keep running back and forward there
Yeah I noticed something along those lines to, but I think it has to do with the way Kongregate displays its game on page. I'll look into it though!