When you apply an intro/outro Magix adds a number of items to you project. In timeline mode each is on its own track -- use the 'solo' button to check which is which.
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In this case the 'INTRO' title is on track number 2 and can be edited like any other title element. Right click on the track 2 object to go the the menu.
I am new to this. I am in Slide Show mode and do not see any track areas. With the rest of the slides I clicked into the text area, but this will not allow me to do that. Thank you!
There is Overview mode, Storyboard mode and Timeline mode, no Slideshow mode. Switch to Timeline mode. You should do most of your editing in this mode. There is a button for this, the location of which depends on the version.
Since you are a new user, I strongly recommend that you read the first part of the manual, Getting started to understand how the program works. Without do so, you will quickly be frustrated with it. But, once you understand it, you will be pleased with how it works and what you can do.
Which version do you have (year and basic, Plus or Premium). If is doesn't say Plus or Premium, you have the basic version.
Did you download and install the Free addons? See under Help, Free addons.
Note this is from MEP 2014 -- in 2015 the mode buttons are at the far right. Note also that the little double camera button (multicam editing) is only available in Plus and Premium versions. Also, in addition to John C.B.'s very usefull suggestions, you should get familiar with the 'Help' option from the menu bar (or 'F1' standard Windows method). Here is the result for a search for 'mode':
Stick with it! MEP has a good learning curve as you go for the more creative options. There are lots of presets and templates as you have found; most all can be modified and in some cases it is possible to create you own versions.
Thank you for these wonderful, helpful answers! I was able to fix the intro and outro in my slide show and I have figured out a few other puzzling things.