Micro Servo Robot

I am trying to make Micro Servo Robot
https://www.thingiverse.com/thing:1136876

When I upload the sketch it says I am low on sram memory and the robot may not function. I am using a DFrobot Arduino Rev 3
The actual message is “Low memory available, stability problems may occur.”
Could I delete some of the program, I am using the sketch from the website above

The original robot used a Arduino Pro Mini, I have a 5 volt 16 Mhz but don’t have a board or connector to hook it to my computer, plus the sram is only 2k the same as the DFrobot Arduino Rev 3

When I am using the DFrobot Arduino Rev 3 the robot tries to function,
but the operation is hit and miss, sometimes it does something and sometimes it doesn’t. I’m not sure what the 2 push buttons on the board do.

I have wired in a store/play button and a pause switch.

I am lost,

Dan Hanson