DS Happy Box compatibility with custom fw/kernel and/or YSMenu

A friend got this old flashcart with a NDS. https://ibb.co/znZmy28 https://ibb.co/LzhpWxg

I managed to retrieve it's stock firmware (shown in this pic https://ibb.co/xhcZmTg) by going here https://flashcard-archive.ds-homebrew.com/r4isdhc.com/ and downloading the 1.19B original kernel.

I think it's a Original-R4SDHC clone since it boots with "Loading...".

My question: is this flashcart able to run a better kernel/fw and/or YSMenu? I didn't try since there are warnings of bricking the flashcart

Also I read the following "Note that Original-R4SDHC clones are very old carts, and often are forced to use their outdated stock kernel, then chainload into R4SDHC-YSMenu for better compatibility." How to chainload?

Thanks in advance