You can have VNAV to a user nominated altitude and a X degree flight path or VS .........BUT this is not in any way certified, it is meant for VFR use only.
For practice approaches in VFR only: Is there a way to have VNAV to user-nominated altitudes to waypoints along an approach, or are user-nominated altitudes possible only for the destination airport?
This reply is very delayed and I apologize. I do have a Garmin 430 that I use however I am having trouble gettin it to interface with the SV system. It shows up when I select it as an HSI source, but the information for course and altitude won't transfer to the autopilot or flight director. I also have a message on the 430 not receiving input data on 429 channel #2. This may be the cause and I can't track down the solution.I gather you are not flying an IFR aircraft with a IFR certified navigator?
If you were or are, then you select the approach in the GTN/GNS/IFD device and it will cross fill to the SV map and HSI.
Unless the Skyview GPS becomes available as a TSO146 Navigator, and the database becomes coded securely, there is no way you will be able to do what you are asking.
I would caution you about building an approach in the FPL menu, which you can do......but that is no way a legal method of flying IFR.
I third that recommendation. I had a similar problem with My GTN and it was a bad setting on the GPS.Do what DBRV10 recommended about the setup & ARINC settings. I have the exact same system and approaches are displayed on my SkyView perfect.