As far as I'm concerned, I dont think non-Muslims are allowed to purchase a Bumi Lot. Not too sure about the Malay Reserved Land though.
Very simply put, Bumi Lots are referring to the % allocation every development must have for their project. I.e. Developer A builds B and state government C regulated that must have D% of bumi lots, so they sell E amount of units as their % of bumi-lot. Developers don't like it as smaller profit margin, while bumi home buyers love it as lower price entry. Investors, no too. Harder to sell later as ultimately Bumi Lots are meant only for Bumis. But I didn't say Non Bumi's can't buy, rather they are just not supposed to buy.
Malay Reserved Lands... well, reserve for Bumi's only. Whatever built on it, only for Bumi's. Not very attractive for developers especially in mixed demography area ie. Kampung Sg. Penchala.