You've got what you've got for hardware. Let's just go with that.
For a primary test of your system (before you build the "current reversal" device I gave you the schematic for), you'll need to test the PS and its ability to move the actuator motor. The load you intend to put on the actuator (2kg), which represents <1% of the capability of the actuator's max, is essentially insignificant.
Note1: The actuator "opening" and "closing" is effected by reversing the polarity of the DC voltage applied through the attached controller box circuit and then to the motor.
Note2: You'll definitely need a fuse in one of the lines (doesn't matter which) coming from the PS to the controller box of the actuator. I would suggest a "fast blow" glass type of no more than 3-5A (the probable max current output of your PS) and buy several. You'll probably need them.
Arrange the wiring needed to get power from your PS to the controller box's input power leads.
Note3: Since you don't (can't, actually) know for sure what polarity is needed to operate the actuator in a direction that will be the reverse of its current position, you're just going to have to guess at the polarity needed and see what happens.
If you are wrong about the polarity, the fuse should blow since a motor that cannot turn (it's at a "dead stop") will be, for all intents and purposes, the equivalent of a dead short. This, of course, presumes that the PS can supply current in excess of that needed to blow the fuse (can you sense some circular reasoning going on here??).
Reversing the polaity of the leads powering the controller box should make the motor turn. If this is the case, then we can go on from there.
If not, carefully note what DOES happen and let us know.