Make sure your limits are off and then try a regen after you zoom extents and zoom extents again.
Are you drawing existing lot lines from legal descriptions or deeds or are you designing new lots. If the latter, try fillets to create arcs.
If you are drawing existing lots and the curves are...
I used to use SMADA all the time. It is a great program that is free (without documentation). Its so simple it doesnt really need documentation other than the help files included with the program. I ofton used it in combination with other programs as a check. Anyway I'm no expert, but it worked...