I have created a package similar in functionality to Iron Python but
for some reason I can't seem to figure out how to setup file type
associations for my custom file types (.esproj & .es). Can anyone
point me to the critical code that I need to have in order to get
these working?

Just so I'm clear, I'm referring to when you browse to a folder with
these files in them through the regular windows explorer and see the
file sitting there. The icon is not setup right. In visual studio when
adding a custom projec then it seems to be working fine but not in the
windows explorer or in the recent project list of the start page. I'm
guessing I do not have a certain Attribute added to one of my
packages...