About your "horizontal plane" rotation - call it the Azimuth (Az for short) movement. Rip it apart and see what is happening. Probably three teflon bearings are attached to the ground board. They may be held in place with staples. Are the staples well under the surface and not scratching the upper board? Is there any central support around the pivot bolt?
Best solution is to buy the pivot kit and three nice big teflon bearings from these folks:-
http://www.astrosystems.biz/pivot.htm
You get four altitude ones as well which I don't think you need in the SW collapsible, but can sell to someone here, I'm sure.
Also you put a layer of Ebony Star laminate under the upper board for the teflon bearings to contact. All solved!
OK, USD/AUD exchange rate too high? Ebony Star too expensive?
First steps then:- check the three teflon bearings. Staples well below surface? No sharp edges that might be catching on the upper laminate? Now give that upper laminate surface a good clean, then a good polish with a silicone car polish. Some swear by a spray of Mr Sheen! I reckon the car polish is best. Next add the "Milk Bottle washer" solution which is the cheap version of the pivot kit above. Read up in here:-
http://www.iceinspace.com.au/63-116-0-0-1-0.html
You should see much improvement.