import function on OSX

[cukal]

When going into backstage --> Import and clicking on Choose File the file dialog pops for a a few milliseconds and almost instantly disappears again making it impossible to select a file.

[sihorton]

I think that this issue with the file dialog crashing was fixed in a later version of appjs. I see TiddlyWiki uses v 0.18 and the latest at http://appjs.org/#download is v0.20. If you are able to download from appjs.org and try with that hopefully the problem will be fixed, if not I can help create a new download with an updated version of appjs for you.