[TxMt] TextMate selectively refuses to open files.

[Michael Sheets]

I don't know why it wouldn't open a single file, it should open  
anything dragged onto it. But when your in a project situation there  
is a reason, it prevents opening of any extension it doesn't know  
about. This is incase you have large binary files you wouldn't want  
them taking a long time to open if you clicked them by accident. You  
can right click on the file (in the sidebar) and toggle the  
"Treat .xxx files as text/binary" option. It will remember it from  
then on.

I'll let someone else tackle the single file instance...