@Eagle1020 and I found that NtRays will corrupt some decompilation results, e.g. ntoskrnl!KeYieldProcessorEx:

Without NtRays:

With NtRays:

This bug is possibly related to the alignment. After I patched the align 2 to nop nop, the result became correct.

With IDA 8.2.230124/8.3.230608 and NtRays64.dll v1.67 (hash 38234666299b9e94ba98d55462da39c7f764d839f6555d03b346226b412e22e6), I cannot rebase ntoskrnl.exe.

Repro Steps

1. Go to Edit -> Segments -> Rebase Program
2. Rebase image to address 0
3. Click OK
4. Nothing happens. It doesn't even print in the console that it's attempting to rebase the program.

Since this is domain specific to NT Kernels, you could make it so that literal values (e.g. 0x80000000) are a drop down form menu containing various defines or enumeration values that match it. I don't know if it's possible with the IDA plugin API but it could be helpful.

What theme are you using?