MDC2250 issues

I'm using an MDC2250 controller and I have 2 issues: 1. I'm controlling 2 motors by serial interface and is working well except that the gate is returning to the 0 position automatically. I'm controlling the motors in position closed loop. Is this normal? 2. When I activate the digital out pins nothing happens. I measure the voltage on them and is 0V even they are active or not. What should I have to check for those 2 outputs to work?

For the first question, keep in mind that if you stop sending commands for more than 1s, a command of 0 will be assumed. In position mode, this means returning to position 0.
The outputs are open drain. So you need to put a load between the output and the + voltage.

For the second issue I was thinking about the open drain but I asked just to be sure. For the first one the 1s time is related to the watchdog value? Is it correct?

If you don't send a command every second or less, the watchdog will activate.
You can disable the watchdog by entering 0 in the configuration value. Or you can extend the timeout period from the current 1000ms to up to 32000ms