WinWWZ has a nice feature whereby if an input source file is not recognised, it will open a dialog asking the user to specify the time (domain) and magnitude (range) thus permitting the app to be "trained" on data sources dynamically. It should then be possible to save that as a new format that the app recognises next time it is encountered. See http://www.aavso.org/data/software/wwz-dataimport.png for an example.
This could be done as a plugin.
See also https://sourceforge.net/p/vstar/bugs-and-features/396/