Portfolio filter not working correctly with pagination

Hi, I found a few troubles when managing the portfolio page.

In first if I set up a page as portfolio on theme options, nothing happens.. I mean it doesn’t show the portfolio on that page.

So I’ve used a portfolio module to get the portfolio up but the filter doesn’t works properly as when paginated, if a item is on the last page doesn’t show when filtering its category unless you’re on page 5. Is there anyway to fix that?
Here you can see: https://staging2.weeboo.eu/work/

Also I’d appreciate if you can help me to add a little margin between portfolio items on the portfolio page and how to make the Category archive pages title smaller (or even take it down). Thanks a lot

Thanks a lot!
Ivan