I have an older LDG AT-100 that does not work with my LD5. When the tuner searches for a match the SWR may exceed 3:1 and the LD5 then folds back power to a level that is too low for the tuner and the tuner then stops searching with now a high SWR. Not sure if your Z100 would have the same problem or even if it is a problem with newer AT-100s.
I use a manual tuner with good results with the LD5. If in SSB I switch mode to CW ( will work in auto ie iambic) and key the LD5. I actually prefer the iambic mode to straight key as I think this might be easier on the LD5. I also prefer to use the scale mode for SWR; for me it seems easier than trying to read the rapidly changing numbers
I have had my LD5 for about a month and enjoy using it. Also have the LNR 3 band Mountain Topper which is great for remote operation. I find the LD5 better for operating at home and portable near the car.
72 Ken WA2FBN