You can't just switch the follower and expect the problem to be fixed... The mag tube (the body of the mag) that uses the blue followers is also redesigned. The 2nd Gen mags with the blue follower have an indented section towards the top that the 1st Gen mags with the orange followers do not.
Contact the customer service dept. of Walther (which is S&W in the US). They may exchange mags with you since their early version mags are known to cause problems with the proper cycling of the action.
Dave, thanks for the reply. My tubes do have the indent, they look identical to the newer mags but for mine having the orange colored followers in them. I did contact Smith on this, they sent new followers for me to use, again the orange variety. Prior to this I sent the pistol and all magazines back to them due to feeding issues, they replaced the barrel and sent all my magazines back, untouched.