"Failed to load mods:Error while sorting items-to-place for entity prototype "iron-trashdump-10x41" (container):item-to-place "iron-chest" count (410) can't be larger then the item stack size (400)"

Mods to be disabled:
Wide Chests (3.0.7)
Squeak Through (1.8.0)
Space-Exploration (0.2.16)

I can load Squeak and Space Exp. if i disable Merging chests. Hope i can get back to making my spaghetti soon :)

Not sure if this will work for you, but it worked for me. I had to delete the copy in my mod folder and then download it manually from the website and add it to my mods folder.

This is caused by conflict between Merging chests and other mod which also modifies chest stack size. If the other mod is loaded after Merging Chests, it will lower the chest stacksize and some chests will not be placable by bots (new bugfix in 0.18.19 I think).

Only thing I can advise is to check mod setting of the other mod to increase this limit to Mergable area limit. Or lower limits in my mod setting so no chest is larger than 400. :(

Thank you for the help. I'm a bit of a dunce and restarted like 100 times to find this. "bonus-technology" has a setting "enable the ability to change stack size" and when i turned it off everything works, except the 1000's of items that are now on the ground, a part of the reason why i liked the mod was stacks of 400 everything. so i fiddled with the values in this mod and what was conflicting was "maximum chest area" set to 1600. i changed it to 400 and now everything works although i have little idea of what this setting does, i assume i can only place 400 chests in a 10x40/40x10 configuration now as apposed to having 1600 in a 40x40?

Yes, exactly. Limit chest area is used to further limit the maximum area a merged chest can have.