I'm attempting to load up some old mod maps with new mods installed, and forge detects an ID conflict and shuts down. That's understandable I suppose, so I thought about manually changing the IDs of the map using Midas or some other program to match the IDs to the configs. The problem is, the forge error log only displays the first ID conflict before shutting down, which means I have no way of seeing all the other IDs that need to be changed. Does anyone know a good way to find and make a comprehensive list of all the ID conflicts between the config and the map?

There's no sure-fire way of determining this, as not all mods use the same config format for storing block ids. Heck, mods could randomly generate block ids on the fly each time it's loaded, ignoring its config entirely. However, if, and only if, they use the default Forge config style, one could write a tool to detect id conflicts.

I'm attempting to load up some old mod maps with new mods installed, and forge detects an ID conflict and shuts down. That's understandable I suppose, so I thought about manually changing the IDs of the map using Midas or some other program to match the IDs to the configs. The problem is, the forge error log only displays the first ID conflict before shutting down, which means I have no way of seeing all the other IDs that need to be changed. Does anyone know a good way to find and make a comprehensive list of all the ID conflicts between the config and the map?

The full difference set is logged in the forgemodloader log file. It will tell you who owns every item and who it believes conflicts.. Also, update forge to a recent version.