Okay, after much searching, I found this and just edited for hex value when I marked the desired Pokemon. But while the stats I altered (or sometimes kept at) 1F (31) turned out fine, the ones I altered to numbers in the 20s... well, lost the 2 and went from, say, 29 to a whopping 9, 25 to 5, you name it. The first time I altered those IVs I saved without realizing whatever mistake the AR must've made (mine's been fucked up a bit), so the second Pokemon I intended to alter IVs with wasn't affected when I knew something was amiss and switched the game right off.
Is... there another hex number that's supposed to represent 2, or is it my AR fucking up on me again?