[I am just another donor of computer power, like you. I am not a Mod, not an Admin, not a Researcher. I am not with F@H, I just wanted my PCs to have a hobby]
I am unclear what you are trying to do, but I doubt you can do it.
The Installer sets up all the subdirectorys the Client uses, even if you got them all created by hand, you would need to insure the client has read/write access to them.
The client does a poor job of noticing what hardware it is running on, the installer finds out what CPU, OS, and GPUs if any, are on your system and write that into a config file. Folders who change hardware later often are reduced to re-installing, as the client gets confused easily.
I am not seeing any advantage to running installer free on any PC I owned, and you are expressly forbidden from running it on other's PCs. You will get NO help on that here.
Once installed, I may go 6 months with only the client running, then pause it, and upgrade the OS, the graphics Drivers, run CCleaner and defragment. Then un pause and pay no attention in another 6 months. (Three of my laptops are used when I do ticketing at a theatre, we do 5 plays a year for 4 performances each play, they need Windows 10 due to an odd ticket printer. Two of my laptops run a BBQ scoring program in a full screen DOS window, So XP is the last windows they can use. I score about six 2 day events a year. One laptop is my daily driver. Two towers are dedicated GPU folders, GTX 1050ti and GTX 1060 They do 95% of my PPD)
https://greenwoodlittletheatre.com/
https://hogsforthecause.org/