Are you using the Instrument Control driver or creating your own script calling the dll directly?
The driver for the PicoScope 2204 does not support the ability to output shots of a waveform, so the only option would be to call the function to output an arbitrary waveform, then call the function to output a built-in waveform and set the output to 0V DC.
You can create an array representing a sin x/x wave in MATLAB (max 4096 values), and you would then need to scale it to -1 to +1 using the normalise.m script if you are using the Instrument Driver package or scale it to 0 to 255 if you are calling the dll directly.
With the PicoScope 6 software, the AWG output will be continuous with the PicoScope 2204 - are you looking to set up a single pulse?
The PicoScope 2206A, 2207A and 2208A will support the ability to output shots of a waveform.