I have created a custom stall in sketchup that I was able to get to load into the game as custom scenery. when I place the item the small circle in the lower left shows the stall but when I place it on the park it only shows its shadow the stall is invisible. can someone tell me what I have done wrong.?

I'm not very good with custom scenery, the kind that you made...however try turning shadows off in the game and see if it helps. Or maybe contact Silvarret on his YouTube channel. https://www.youtube.com/channel/UCkSWAX1...yRHWn17W0w
Not sure if he would be able to help you or not. He's done so much with this game so it wouldn't hurt to ask.

not good with cs either but to me it sounds like it was imported wrong

This sounds like it's NoLimits if you used Sketchup to make it. Which game are you using for clarification?

I'm playing rct3 platinum and I git it to show I was to far away but now it crashes the game so I'm going to play with it a little to see if I imported it wrong. I built another stall right after it and it went right in. I'm thinking I may have too many poly for it to work.

I'm not sure how to increase the draw distance on objects, or how to decrease poly, but good luck.