Hi,
If you want to play with it, here's some example code for you.
string fullPath = @"C:\users\user.name\Documents\test.png";
string directory = Path.GetDirectoryName(fullPath);
string fileName = Path.GetFileNameWithoutExtension(fullPath);
string extension = Path.GetExtension(fullPath);
int count = 1;
string newFileName = fileName + count + extension;
string newFullPath = Path.Combine(directory, newFileName);
I can post a bugfix release of @TechnoRobbo's plugin sometime this weekend.