It seems impossible to get an older version from GitHub using SourceTree, without setting that version as current.. which would be disastrous.

Perhaps this is an error,

If I select multiple files I can only select "Open Current Version" and if I do it opens in default application,

If I right click on a single file I can select "Open Selected Version", it tries to open in default application, but with wrong parameters.

(please do not ask why I need this, a long story, but I do.. and a simple task when I was using Tortoise with SubVersion)