Using the app is very easy. We would suggest you checkout the video on this page.
Split Screen Pro App is a menubar app. So when you start the app it starts in menubar. So if everything is fine, you shuold see 
icon in menubar.
If you don't see it, please contact us along with following details:-
1) Your MAC Model
2) MAC Os Version
3) Screenshot
Split Screen Pro works with most application in which standard window types are used. Applications using non-standard windows may cause unexpected behaviour or may not work at all. Here is the list of known "trouble" applications.
If you have some interesting feature request then you can submit it here.
We strive to make all our customer happy. So give us a chance to straight things out.
Just Contact us and we will take it from there.