Glad to hear that you got it open

yes adjusting the cable may help
in general lubrication is what is needed

latch receiver needs some grease


make sure the small screw is tight as it fasten the cable holder

underneath



moving parts of the latch also needs some grease including plunger rod




Then of course the handle pivots use a little oil
* If the cable is rusty that's a big problem, try soaking it in automatic transmission fluid
* If the cable clamp is loose that's another big problem