I noticed that my install of MyEclipse had a log entry that it could not find the .myeclipse.properties file. Where is it :)?
This is a "dot file" that should be in your home directory. A little Googling indicates that this file has your subscription information so you don't have to provide it for every workspace. Typically this file should be created on installation; if it wasn't you may have a permission problem. Hopefully the log has more details for you.