WattUp

I would check the physical motor install, verify bearings are good, check runout / alignment, things like that would cause the drive to be working too hard. Also recommend plugging into the drive and using the software to monitor the drives performance. it might point you in the right direction.

  With that low number of I/O  I would bet its mostly an order of operations & timer based system. It might be a good idea to try to create a map of the functions you KNOW it does and build from there.  A scope or meter on the outputs to get a timing and order. if there is a HMI look for any settings / parameters.

Glad to help.

PLC Parameters > Device Tab. Set a start / end address for the Latch 1 / 2 as needed.  Latch 1 is data retained during power cycles but reset with Latch clear command. Latch 2 retains data always.

I created this program to help me remember how to set this up. EthernetLink.gxw

Your screenshot shows un-compiled code (as well as an incomplete rung).  First complete the rung by tying Y0 contact to where it needs to go, probably a vertical line before /X1. Then compile your code <Compile Menu> <Build> (F4 - Shortcut), if you are online with a Running PLC than Shift+F4 for an online build.   Then save your file.  

This ^ Set your button with two actions, one for the pump switch and another for window screen = 0.  

you could try to uninstall with Revo Uninstaller. It includes extra steps after uninstall that scan registry and left over files for a true clean slate.

UL508 : Standard for Safety of electrical control panels.   

I believe if the programs are linked to a navigator file, you should first open navigator, and then open the HMI from there. It might be upset if you open the HMI file directly because navigator has the files linked.

EthernetLink.gxw This program was my base for setting up a similar communication link.

Little more detail in case you are new to the Mits PLCs M are basic internal relay bits.  D are basic internal Words L are Latched internal relays (their state remains through power cycles) X/Y Obviously inputs & outputs T are timers C are counters Z are pointer modifiers i.e. [MOV K150 D100Z1] would move value of 150 to D100+(Value of Z1), so if Z1 = 10, D110 would 

Could you instead make 1 button, but change the function in the PLC depending on the condition? You can even make the Text change based on the condition too. 

I had a similar symptom 2 years ago. We had a terminating resistor installed across DA-DG instead of the correct DA-DB.  Just one more option to check.