[PRTL ED] How I do it?

[TheGreatCthulhu]

About DustDebris and SmokeDebris box emitters (Box Start): Min Position (x, y, z) and Max Position (x, y, z) basically just define the invisible box (or volume) from which the particles will spawn, in the (I guess) world coordinate system - by specifying two of it's corners. Since particles are already setup to float towards the portal, you just need to move this box area to lie somewhere along the x-axis (the red one), or somewhere where's appropriate in your case - but not to far, so that the particles don't die out too soon.

An easy way to figure the values out is to pick some center point for the box, for example (5, 0, 0), and then for the Min Position you subtract some values from that (5 - a, 0 - b, 0 - c), and add those same values for the Max Position (5 + a, 0 + b, 0 + c) - so you'll have a box centered on (5, 0, 0) width the dimensions of (width, height, length) = (2a, 2b, 2c).