When indexing, is there a colored highlight option for the line you are working on to keep track where you are?
Yes there is! At the top of the indexing screen, to the right of the tree, you will see three drop-down menus: Batch, Data Entry and Help. Click on Data Entry, then scroll down to Show Ruler. You may have to adjust the indexing page to find the ruler and the ruler has to be moved manually, so just click, hold and drag to move it.
Yes, You will find it under the Data Entry heading at the top of the page Show Ruler.