Has anyone ever seen this surface condition before?  

Has anyone ever seen this surface condition before?

Hello Gang. I should probably put this printer out by the road at this point, but it was my first printer and although it’s now painfully slow and about 10 generations behind, I’m emotionally attached. 
 
So, it’s been in storage for a couple of years, recently pulled out of mothballs and cleaned, lubed, and updated. I’ve printed probably a dozen models or more on it in the past few months and while not up to modern standards, it’s been acceptable. It seems like these MultiBoard bins have been deteriorating from one batch to the next and I can’t figure out why. No fans in the area, filament (PLA) is dry, it’s feeding out of my Eibos dryer (powered off but loaded with desiccant) which sits right next to it. I’ve dabbled with nozzle temp and flow rate a little but nothing seems to change. The worst of it is in the left back corner (as you stand in front). As you follow the print towards you the left sides improve noticeably. The closest face of the bins to the observer are ok. The right side of the plate, along the whole length are fine, and the back is very good. There’s something odd going on in that back left corner. 

Hopefully one of you folks will see the pics and say “yeah dummy, you’ve mucked (blank) up!”, but I’m at a loss. Help save the old dodger from the glue factory please.