Jango, good to see you here again mate. I am in the process of updating the Tuts but just been very busy with work.
If you want any extra to run after another extra, you dont need a menu, all you need to do is load extra into its own Movie1, then Movie2, etc timeline. In the Connections tab, for the Traget of the End Action of the LAST chapter of Movie1, just set it to first chapter 00:00:00 of Movie2. On playback, when Movie1 ends, it just automatically starts at Chap 00:00 of the next movie and it all run seamless.
As for JPEG Menus, I use Paint Shop Pro but any other graphics edit can ge used. For a 4:3 PAL menu, make a blank 720x576 picture and import what ever pictures and add what ever text you want to this pic. Dont go to close to the edges though as the TV screen chops these off. Save it out. Then just load it into Maestro as an Asset and grag to the Menu1 timeline window. Make sure that window is Maximised else you may not see all the controlls. A 19" Monitor running at 1280x1048 is recommended for Maestro ! Then with the mouse click and hold and drag a square around the first option of the Menu. Do the same for the second option, then 3rd etc. Do them in the order you would normally navigate to them. Go to menu Advanced tab and click Auto Assign. This allows navigation of the button using your remote control. In the Colour Mapping tab, I set the Button Selection buttom Brown colour from 8 to 3 or 4 as 8 is to dark for me. In the Connections tab, link the end action of each Movie/Extra to run the Menu again. So when they finish, its back to the Menu to make another selection. Also link the Traget dor each of the Menu buttons to the first chapter of the appropriate Movie1, Movie2, etc. Set First Play to Menu, of course, not to the movie1.
I think I've covered the basics there, hope you can follow it.