Hi Jon. I'm Greg, 10 years awarded Windows MVP, specializing in Installation, Performance, Troubleshooting and Activation, here to help you.
Try these fixes for the regedit error:
https://www.techilife.com/cannot-create-value/
https://techcult.com/fix-cannot-create-key-erro...
https://becomethesolution.com/cannot-create-val...
https://superuser.com/questions/986888/why-cant...
https://windowsreport.com/registry-error-writin...
(Avoid ad links which intrude into editorial copy, especially avoid Restoro, PC Repair Tool and Reimage ads)
https://www.howtogeek.com/262464/how-to-gain-fu...
https://www.youtube.com/watch?v=wiZ6rry9AoI
https://www.youtube.com/watch?v=TKEIvzMedl0
Have you tried updating the drivers from your Lenovo Support Downloads web page here: https://support.lenovo.com/us/en/
There are suggestions for controlling brightness from Lenovo here:
https://support.lenovo.com/us/en/solutions/ht07...
Also try the suggestions here:
https://www.gfisk.com/lenovo-laptop-display-is-...
https://www.drivereasy.com/knowledge/how-to-fix...
https://www.gfisk.com/lenovo-laptop-display-is-...
https://smallbusiness.chron.com/adjust-brightne...
https://www.elevenforum.com/t/adjust-display-br...
For more specific suggestions you can contact Lenovo Support or Forums:
https://pcsupport.lenovo.com/us/en
/contactus?linkTrack=footer%3ASupport_Contact%20Us
https://forums.lenovo.com/t5/English-Community/...
Feel free to ask back any questions. Based on the results you post back I may have other suggestions if necessary.
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