We are currently working on development of SlickEdit Core 3.7.0...which will be built on the recently released Eclipse 3.7.0. It will "officially" be compatible with versions dating back to Eclipse 3.4.x. Eclipse 3.8, as far as I know, isn't slated for release until next year, parallel with Eclipse 4.2 I think. Even though eclipse.org makes the stream builds available as soon as they are producing them, we don't test compatibility with the platforms that they are currently developing. You are welcome to try Core 3.6.1 (and Core 3.7.0 when it is released) in the Eclipse 3.8 environment...and see if it works. I don't have any great reasons why it shouldn't work, but just know that there could be some API changes that break our compatibility...it does happen sometimes with their major upgrades.
Hope this helps,