You can select all the files you want to combine at a time from the files grid after selecting the folder in which all the files are kept. You can select any number of files at a time to be combine or merge in to a single multi page tiff file.
You can search for specific files that are of specific size or were created in a specific time period. Just select the options from Advanced Search Options and you will get the files you want .
You can even hide the advanced search options if you have no use for it. This gives you a lot of extra space to see all the files that are present in the files grid.
