Never use any force on any part of the synth at anytime, some of them are so cheaply made that the plastic over time gets brittle and the last thing you want to do is break a face plate.it could also cause a short rubbin the coating of fa wire. Just take it apart, takin pictures and noting which screw goes where. You will have to take out the keyboard contact circuit board[s] maybe, the main board for sure to get to the display board. Use bright light and a mag glass and just keep lookin around the area of where the ribbon cable attaches. Look very well ,don;t touch anything, even walk away and come back look hard again ,your problem might be very small and hard to locate, but could be just as simple as the ribbon isn;t seated in its connection block. They only go in one way and it can only be the one cable that fits that block Its fail safe. Pull it out first and look at all the pins and in the holes in the block a piece of dirt caught somewhere could be the culprit. ALways use the K.I.S.S. principle.Since you have the board on a towel and foam blocks or rolled towels on the ends to protect the bender,you have an air gap.To reach the display plug it up and power it on and use a small mirror to see what the display is doin after pluggin the ribbon back in before you add power. Its possible theres a wire ribbon for lcd controls and a small 2 wire block for the LCD power.If he lcd seems to be workin normally now, the ribbon was stretched or pinched by the back cover meanin some one has been inside it before and didn;t put the cables back in the right place. Displays almost always give a " death rattle" warning sign when they are fixin to go out ,but your problem is not a death rattle/symptom.If you still have to push on the diplay to get it to function and you can tell someone’s been it it before you then its a good chance that some pins in the ribbon are bent and not makin contact, you can try to straighten but a new ribbon might be in order. It could also be the female end ,the block on the lcd c.board,which would mean replacing it. The whole LCD. These are generic parts and theres hundreds to chose from l at a elec supply site like digi-key or mouser. They are identified by the amountof lines and the number of characters in each line and also by its viewing window size and overall size. Not an expensive part unless you go for the fancy backlit color change models…Doubtful there would be any soldering work in this display swap. If you have more than one synth that has the same display configuration, you could just buy one then swap out to the new one and see if you have to press on the faceplate to get it to work or not and if its not needed just put it up, you’ll use it one day and I;ve done quite a few for guys that couldn’t see the stock display on a dark stage plus folks are color blind too ,so upgrading a display though its not broken happens. This info is just basic generic guidelines and will vary due to the amount of keys and the display location on the face plate or even more different if its a rack or module type. Just remember to take pictures ,label screws and know that the plugs only go back one way ,there should be no forcing anything back in, the same way there should be no tuggin on a cable to get it out. Have a can of deoxit or CRC Qd contact spray handy and some dielectric grease handyand do a good cleanin and before starting check the battery voltage. The owners manual will tell you how. Put a new one in if its down any more than say 1/2 -to 1 full volt. This might mean soldering in a battery holder,then changing memory battery is easy pop in and out, and the owners manual will tell youhow to reload the stock sound, you will lose anything you created unless you back it up on another device. Alot of synths take the standard cr2032 coin battery, good for 5 years plus. do the work away from other famil y members [especially kids and animals] little hands and paws and fur get in the dangdest places