Slow processing since 14.7 download

[#1]

I'm working on a 10 min video and the processing is really taxing my iMac.  nothing more than a few subtitles. 

4.2 GHz Quad-Core Intel Core i7
32 GB 2400 MHz DDR4
Radeon Pro 580 8 GB
SD hard drive for storage

Never happened with other versions.  I tried downloading the fix for 14.7 but it doesn't recognize my Creative Clound account and asks me to either purchase PP or start a trial.  How do I get access to the fix for 14.7.  Thanks

[#2]

I'm working on a 10 min video and the processing is really taxing my iMac.  nothing more than a few subtitles. 

4.2 GHz Quad-Core Intel Core i7
32 GB 2400 MHz DDR4
Radeon Pro 580 8 GB
SD hard drive for storage

Never happened with other versions.  I tried downloading the fix for 14.7 but it doesn't recognize my Creative Clound account and asks me to either purchase PP or start a trial.  How do I get access to the fix for 14.7.  Thanks

[#3]

A 4-core i7 is perhaps older ... what's the age of that machine? Premiere is built to run on more cores these days. One major internal ongoing process is updating the code ... each version dropped will have some updated code, and that will make it more difficult for older machines to work with Premiere.

But more stable on newer machines.

Neil