To convert a project (or any folder for that matter) to a new AS version we have the Convert Project tool:
_AstM13ProjectConversion
As well as for projects, I find this useful for converting my Prototypes for various clients, Standard Part Templates, Special Parts etc.
When running the tool:
First pick a source directory - this is fine.
Options to tick or un-tick certain files - also fine.
HOWEVER,
You are then forced to create a backup directory location, a log file directory location and a log file name.
Generally I don't want to do any of this - I normally back up manually before I start as that's the quickest way.
Please let us proceed with the conversion without filling these fields in!
Maybe via MT default to make them non-compulsory or even a default location and filename (perhaps to user profile Temp folder) so user can simply action the conversion without having to waste time creating filepaths that are just going to be deleted afterwards.
The current behaviour is spoiling a useful tool to the extent that if there are not so many files it is quicker to manually open and save the files to convert them, which is a shame when we have a tool that is supposed to make it quicker!