Not sure if this is intended or not but i cant use prod modules with any of the effciency recipes selected

are you sure?
remove all mods except Crafting Efficiency, Creative Mode Mod, and omniLib and try again. all recipes should be able to use prod modules.

if not, i need a list of what mods are enabled, and what mod settings are in place.

Ive turned off all my mods and only have omni lib and CE enabled on a sandbox cheat world and still having the same issue. Ive left all the CE settings as default

what version of the mods are you using?

Version 0.0.24 For CE
Version 2.0.46 For Omnilibrary

then....productivity modules should work......

i've verified it multiple times.

Im not sure exactly whats going on
Recipe selected
https://steamuserimages-a.akamaihd.net/ugc/951846164382415402/C41287C970334D83261B267BB2617AE19E8F3148/
Attempt to put module in
https://steamuserimages-a.akamaihd.net/ugc/951846164382419611/A0C3DE12DC3DDD475E67CA777763B15A659E8D7B/

Heres my modlist
https://steamuserimages-a.akamaihd.net/ugc/951846164382440338/78611C7E7D27B975C858CE3BA25751096D2D598F/

https://steamuserimages-a.akamaihd.net/ugc/951846164382440706/F056491B455940E68C3851166CEBE73F357FBB19/

I do have the same problem

Factorio 0.16.x Latest 0.16 Experimantal
Crafting Efficiency 0.0.24 and before that 0.0.23
Omnilibrary 2.0.46

ugh found the problem. I'm using an edited version of omniLib. (one i edited a few weeks back and forgot what i did to FIX this EXACT issue.
i'll message zelos about it now...

to fix productivity modules not working on anything recChain makes, insert code into RecChain of recipe-generation.lua:2134 of omniLib (for until zelos corrects/updates)
if self.add_prod then r:addProductivity() end

before the line: if self.isTile then r:tile() end

(sorry about that. it was about 3 weeks ago i made the change inside omniLib while trying to resolve this issue, fixed it, forgot what i did to fix it. then got sidetracked with thanksgiving trip, then got sick, and came back, forgot that i had edited it in the first place or to mention it to zelos on what needs a fixin') but the next release of omniLib should fix it up.

All good im just glad you knew what was up cause i thought i was some kind of special case :) Thanks for the work

Thank you very much

Any ETA when this fix will be applied permently to OmniLib ?

..when EmperorZelos releases omniLilb 2.0.47, or whenever he adds those lines into the omniLib code so the add-productivity code works ;)
https://discord.gg/WQYks7W