Here is what I've tried:
1) Drop a panel on the form, set its size to 200x200 / BackgroundImage to RoundMeterBackground.png / BackgroundImageLayout to Stretch
2) Drop an AnimatingPictureBox on the form, set its size to 200x200, don't set BackgroundImage but set the Image to RoundMeterNeedle.png and other settings from this post
http://advancedhmi.com/forum/index.php?topic=585.03) Either drop another AnimatingPictureBox on the form and set it as you wish or create a copy of the AnimatingPictureBox you just created in the previous step and possibly change its PLCAddressImageRotationValue address and the scale max values
4) Move the first AnimatingPictureBox to the panel and then do the same with the second AnimatingPictureBox
5) In the MainForm Load event put this line:
AnimatingPictureBox1.Controls.Add(AnimatingPictureBox2)
Check the attached pictures for the start and the end result.
I just did a quick test and it appears to be working fine. Tried the same scale for both with max value of 30000, 1st needle responding to N7:0 and the 2nd needle responding to N7:1 which was just (N7:0 value + 5000). Also tried different scales with max of 30000 for N7:0 and 1200 for T4:0.ACC and the needles were independently moving from each other.
Not sure if this is 100% what you were looking for.