There is a whole new format for groundobjects. Your mods are not gone you just have to "reformat" them to the new way. No more is a groundobjectdata.ini needed, now you can install just like aircraft. Open up the main.ini of whatever groundobject you want added. Add these lines at the top....(xxxxx being the name of the object)
[GroundObjectData]
ObjectFullName=xxxxxx
ObjectDataFile=xxxxxx_data.ini
So for example
[GroundObjectData]
ObjectFullName=FROG-3
ObjectDataFile=FROG-3_data.ini
Once you have converted all of your objects delete all and any groudnobjectdata.inis and any data.ini you have hanging outin the main groundobject folder as they are no longer needed.