Honestly other than that error everything else was fine. I did not have any resolution problems either so I assume the primary issue with no variable resolution was tied to scale and layout. If you really wanted to try to add variable resolution I am sure you can ask someone who could guide you in how to do it in TyranoBuilder.
Oh and since this game is primarily Spanish I don't mind if you translate this guide for those who might not understand English perfectly (by the way your English is amazing. Makes me wonder what kind of hell you went through learning this rather deranged language.)