There are many things you can try.
1) Lower your graphics settings. I suggest keeping everything on medium except for brick FX, otherwise you cannot see undulo bricks.
2) Get a better internet connection. I know its out there, but this works.
3) Get a better computer. Again, out there but it would help.
4) Clean up RAM space. This mean emptying internet cache, game cache, and basically anything else that is in temporary storage.
5) Get rid of some un used add-ons. The most common problem with blockland loading slowly is too many data blocks. Disabling some add-ons will allow blockland to run faster and smoother.