RomRaider

I've found over the past few years it's increasingly annoying to have to run 32-bit JRE. I have apps that need 64-bit. Generally everything works with both but with occasional hiccups. Also RomRaider issues a warning if 64-bit JRE is installed, even if 32-bit is also installed.

Is 64-bit JRE support coming?

Not likely. There's drivers that are only available in 32bit form, such as the Openport 2 driver. This can't be accessed from 64bit Java. Also other libraries outside of RomRaider are only 32bit at the moment.

What you can do is install a dedicated 32bit Java 8 along side RomRaider. Use the ZIP versions of both Java and RomRaider.
In the run.bat file adjust it to use the dedicated javaw.exe.

RomRaider isn't looking at what JREs are installed. It's looking at what JVM it's actually running in. Both can be installed, but typically in that situation the 64-bit one is used by default by the O/S.

If you have both installed already you can do a variation on Dale's solution with your existing 32-bit JRE. In run.bat change "javaw.exe" to the fully-qualified path, such as:

"C:\Program Files (x86)\Java\jre1.8.0_241\bin\javaw.exe"

Be sure to use the quotes.

Just recently installed Java 8u311 on a recent install and didn't install a 32-bit version of it after that, RomRaider didn't give me any error's like it used to with past versions. Might be because I installed the latest version of RR(0.8.2) since I had v0.5.9RC3 with custom code for Nissan ROMing. Might be just me but if anyone's having issues with getting a 32-bit JRE to work then get the latest zip of RR, worked for me.