There isn't a specific template as such. AT certainly can import data exported from Tinderbox (Note: Storyspace users would need to open their TBX in Tinderbox and export from the latter). Bach at TBv5/ATv1 I did quite a lot of testing for AT's author to ensure the apps had reasonably interchange. I also did some limited tests during the AT2 beta.
AT2's help page for import is at
http://www.aeontimeline.com/support/importing/ - see the section 'Rules for CSV files' and note the comments about escaping (straight) double quotes used in exported strings. The latter need escaping by doubling and that's something TB can't easily do (depending on the exact context - IOW it's not a simple yes know).
I believe AT used to support the easier tab-delimited format for import but it looks like AT2 dropped that.
The general approach is to write an
envelope-and-letter pair of templates. Use the envelope template on the container (agent?) holding your notes to export. The letter template is then used with each data note you wish to export. Due to the vagaries of the CSV format, if any of your data included straight double quotes in them you may have to post-process the export and escape any
" characters.
If you want guidance on how to make the sort of templates described above, I suggest starting a new thread in the 'Exporting from Tinderbox' section of the forum. If doing so, it might be useful if you can cite the attribute('s) you wish to copy across or even better, post a small TBX we can use as a reference example.
I hope that helps.