ALBW should work fine as a CIA file on the 4.x "CFW". Before I switched to Gateway, I ripped my own cart and converted it. If I recall, it ran and saved fine, but pressing the home button would occasionally freeze the system. I highly suggest moving away from the CFW though, as it's very unstable, and limited in what it can do (it can play some games from 6.x and 7.x in CIA format, but not many, it's on a per-game basis, it cannot access the eshop, it is not region free for CIAs (meaning you have to seek out "region free" patched CIAs) or retail carts, and it cannot play retail cartridges newer than your current firmware version), if you can. You can access the eShop if you also use the MT card's emunand, but with the new 9.5 update that came out recently, it has some bugs (some games boot in Japanese, Majora's Mask freezes if it's an out of region cart, or something to that effect).