From Sitefinity 3.6 we use embedded templates and its name differ from those one used in older versions.
1. You should map external templates. Please read this KB
2. The procedure for creating custom metafileds is the same, so you can follow the article from our dev manual.
For instance if you want to map templates for creating and editing News content items you should map - NewsItemNew and NewsItemEdit templates located under Admin folder of the zip archive with external templates..
the Telerik team