Mate if you need any hep ask me. I know almost everything about it as i used it for a long time until i got PS.
One thing which is annoying is the layer modes. There are not many and if you want to save as a PSD file some of them won't work. Dodge, addition, burn etc. If you need any help with it just ask

I would also recommend saving a lot of the time because it crashes a lot. At least when i had it it did.
There is also not many tools. It has the basics but some of the are missing like the pen tool.