Hello HSE and all members old enough to remember me,
I cannot help you with that problem, but looks you have already found a solution. Nearly three years passed since I serious programmed with MASM, so I'm a bit rusty. In addition, currently I have little interest in this kind of programming, so I will not continue the development of the SmplMath macros. The same applies to the "real_math" macros, even if I have recently used them to quickly calculate some big constants. After all these years, the code of the SmplMath macros looks ugly to me, not just under the hood, but also in the public interface. I can't think what came over me choosing names like "fSlv" for macros that actual evaluate some expression ... or OMG "fSlvTLS" (local variables == Thread Local Storage? WTF

).
Anyway, I was always impressed how stable the SmplMath macros work and it is nice to see that there are still some users!
To cut a long story short: You can take over the development if you are interested in it - I would supply you what I have on my disk. I make you the same offer for the "real_math" macros (which are well written IMO).
Kind regards to all
qWord
PS: Please do not be upset if it takes some days to reply you (hopefully not weeks)