Difficulty getting into reverse and jumping out of reverse are probably not connected.
The former can be clutch spin caused by low oil level, tight spigot bearing running clearance, clutch not bled preoperly, or the clutch linkage incorrectly set.
Jumping out can be caused by play in the gear linkage, incorrectly adjusted reverse selector stop bolt, selectors or reverse light switch, or the carpet bunched up behind the lever.