If your on windows you have to run shrink-a-os as administrator. Right click and run and that will make shrin-a-os work correctly. If you just double click it to open it it will not actually delete anything that you selected to remove
To be real honest with you I don't even see how it is possible to add application memory by removing files from the drive?? I could see how it could give you your 5mb back of free disk space, but not application memory.