Question about downloading isos on mac and running them with dolphin

[cvl25]

So I'm trying to run f-zero gx with dolphin on my macbook. I extracted a few of the rar files from the download, and each one has an iso in it. Does it matter which one I use, or do I have to combine them or something? Because when I run the game there's a lot of screen tearing, especially on one specific course (sand ocean). Should I try a different iso, and how can I permanently add it to my dolphin library?

[Zorlon]

when you extract from a multi part archive e.g. an rar file that has more than one part to it, when you extract the all the parts are extracted and should produce a full size disc image

As a general guide extract from the first part, the first part depends on the type of split archive, most often it's just the first numbered file but on occasion this general rule is broken when a master file is used as well as the numbered files e.g. *.r00 *.r01 *.r02 ect ect & *.rar in that case you extract from the *.rar file instead of the first numbered file