audacity won’t run after recent update. Recording/ playback issues also.

Hi. I’ve been using audacity on my macbook pro 2011 for years without any issues up until the last 2 years. When I recorded mixes or anything thats a couple of hours long, when i play it back there are skips in the playback. No gaps but it jumps forward a second or two. That is highly frustrating if i have stood there and made a mix for a couple of hours only to have to delete it because its unlistenable.

Recently i upgraded my OS to 10.12.6 (for other reasons) and still had the same problems with audacity. So I Looked on a thread on here and realised that there was a newer version of audacity. After downloading the latest version (2.3.0) i have struggled to open the program (icon bounces and then stops without opening).
It did randomly open and i managed to record a couple of hours worth of music but i could only record onto my internal hd (which is 45gb from being full) and also took me 3 attempts to record without gaps appearing in the music. When i tried to adjust my preferences in order to record to my external hd, it asked me to reset audacity so changes would be saved. Having done so i now cannot open audacity back up again.

I have deleted the old version including everything in the: go to
~/Library/Application Support/audacity As read on another thread & Have tried downloading the latest version a couple of times.

Its really annoying.
Please help. Many thanks.