I’m hopeful that I’ve understood your first Q correctly.
You’ll need two Animator properties, one to control Opacity and the other, Chracter Offset.
Select the Word Animator 1 and press the Return key. Change it’s name to AnimatorOpacity. While it is still selected, goto Edit->Duplicate. Select the duplicate Animator and hit the return key and rename it AnimatorCharacterOffset.
Upon duplication of the Animators, AE will only retain the last Animator prperty. In the case for the decoder, it will be Character Offset.
Select the AnimatorOpacity and delete CharacterOffset.
You should now have two Animators, one for Opacity and the other for Character Offset. Each Animator has its own Selector Range. The Selector Range will allow you to complete the Opacity animation independent of Character Offset, which has itw own Selector Range.
Drag the last keyframe for the RangeSelector for Opacity and drag it to the 10th frame on your timeline.
Hopefully, you’ll get th eresult you want.
As for the second Q pertaining to the number of changes Character Offset goes through, just change the default value of 19 to 50. Take note that the speed or the number of offsets are also dependent on the time it takes to go from points A – Z. If there are insufficient frames going from points A – Z, then AE will zip though and drop a few offsets while trying its best to adhere to the max and minimum ranges. Where 0 would be the minimum and 50 the maximum in your example.
HTH
Roland Kahlenberg
https://www.broadcastGEMs.com – Adobe After Effects project files
https://www.myspace.com/rorkrgbspace