My modules are often red when I bring them into an app. I am having a hard time getting to the bottom of it because when I go into edit the module, there is nothing wrong. Also, from the context of the app that is using the modules, there are no console errors that mention the modules that are red. I have a feeling the red is an indication of a problem that is manifesting in modules outputs not evaluating properly all the time.
Hi Shawn! If you hover over the module's title, does it show any particular error?
It does not. It just shows the same title in the little tool tip popup.
Would it be alright if I stepped into your org to try a couple things? I asked the eng team that built modules if they knew what might be happening and it seems like taking a look directly at your modules would be the best next step 
Yes no prob. @Kabirdas has mentioned there may have been a fix that rolled out yesterday. I haven't had a chance yet to properly interrogate our things to see if it fix anything. I have been getting fairly good success by using js queries in the app that feed one modules output into another's input through a modules query input. It does make for a bit more for thought in a modules exact use case though.
@victoria I can now confirm that I am still seeing the red error indicator on most of my module when they are loaded into an app. Of course, only during edit mode. I am still not seeing any actual negative impact though. I am wondering for some reason(not really sure why) if it could have something to do with a module once having an input but then removing it while the app was still set to load some data into it. Is the app somehow stuck on trying to feed something into a modules input that no longer exists in the modules? I think most of my modules certainly underwent this condition when first creating them while I was experimenting to get my head around how best I was going to be using them.
@victoria So, with that nice fix that just came in for modules outputs, I realized my problem app consists of just two modules and there is no queries at all in the app. I just deleted both modules from the canvas and dropped the modules back in. After linking them back together, there seems to bee no issue now. The modules no longer indicate a ghost error. 
Woohoo!!!
So glad to hear you've been released from depths of module purgatory. I know you've had quite the experience with modules as of late and I'm relieved to know everything seems to be working for you now.
Thank you for the update!