I tried the Lite C with the A6 but of course it cannot run the wdl files. Will the Lite C purchased version be able to re-use my files from A6?

P.S. Of course I read the docs about the #include and variations in code (not all but enough).

No it won't. Lite-C is a (almost) completely new developed language. I don't know, but I thought there would be converters for WDL -> LiteC

Buy A7 to use Lite-C

he is asking if he can use his wdl files with lite-c(the paid one).

Feature page says no. You need at least a7 extra run wdl files.