I'm using Atmel Studio 7, but I don't use wizard to create new projects. I usually copy a small part of ASF3 libraries (that can be downloaded as stand-alone zip) in my project folder. Mainly I'm interested in include files (definitions of registers, fields of registers and so on). I don't really use high-level drivers of ASF3.
For a new project I will use SAMC21N part, but I found it isn't supported in the last version of ASF3 (that is asf-standalone-archive-18.104.22.168.exe). Is it really so? Doesn't Microchip update ASF3 with new parts?
In the past Atmel moved from ASF3 to ASF4, but I didn't follow this migration. Recently Atmel was purchased by Microchip so now MPLABX ID supports Atmel parts. What do I do? Should I switch from ASF3/AS7/gcc to MPLABX/Harmony/XC? As you can understand it will not be trivial and I'm not sure it's worth it.