M Mount Wide Angles and RAW - X series

I use a Zeiss ZM 21mm F4.5  and a Voigtlander 15mm on a Nex 7 and of course run into color shift issues. Looking to pick up a either a Nex 6 or a XE-1 to avoid this issue and keep the 7 for the longer end. I have two questions:

1. Does anyone use either of these lenses on an X series and if so is color shift an issue?

2. What do RAW shooters use to convert files?

Many thanks.