What can I do to get my Rainsoft Classic Apollo Q2 working again?

Hi, I am need of help trying to figure out why my water softer system will not work. My Rainsoft system was giving off a continuous beeping sound. I had a service guy come to check it out. It was determined that I had a leaking water pipe. The system had been shut off and unplugged. It had been over a year before the pipe had been repair due to me being ill. Although the leaking pipe had been repaired, when I plugged the system back in, I ran into some other problems.
1. It had a continuous beeping sound.
2. It only showed the four blinking red dots.
3. It wouldn't display any new settings input info for the display timer

I had a service guy come check it out again and they indicated that it was not able to run anymore. (He also claimed that the computer board was shot) So they suggested that I get a brand new one ($2000). Anyway I decided before getting a new system to try to see if this one can be refurburished.

I unplugged the the system and replaced both the 9 volt battery along with the fuse and replaced old salt with new salt. Once I plugged it back in again, the flashing dots disappeared and so did the continuous beeping sound. However, I now am hearing an intermittent beeping sound. Yet, no numbers will show up on the display panel / timer. Can someone help guide me with what to do and what other parts I should replace to help try to get it working again?

Ps if the computer board is shot would the dots be flashing ever?