Don,
The IMAC rulebook and judging criteria is available at:
http://www.mini-iac.com/DesktopDefault.aspx?tabid=90
You will want to concentrate on the Flying and Judging Guide portion of the rulebook for the judging criteria of the figures.
Entry and exit in Figure 1 of Known A do not have to be at the same altitude (pg F&JG-34 and -35).
There is no centering criteria for figures in IMAC.
Regards,
Anna Wood
Tucson Aerobatic Shootout
Scorekeeper and Webmaster