POI visualization height

People can't see the icons because they aren't zoomed in to 300 ft or closer. So I think if there was a way to change the viewing heigth in would have been mentioned. So from that stand point I will say no, you can't adjust it.

The levels at which icons appear (and disappear) aren't customisable for Custom POIs on the current Nüvis. They are influenced by the amount of map detail you have selected and the type of map display (3d/2d etc).

There are 3 ways I can think of, to make them more 'prominent' - each with Pros&Cons.

1. Embed copies of them in a custom, transparent map. Obviously, this is a whole new topic to learn, but gives the most flexibility. Unless you want a symbol from the default built-in set, that is yet another issue to address (using 'TYP' files?).
2. Make copies of them as Favourites, since these are displayed 'sooner' than Custom POIs. You are limited to the built-in symbol set and a maximum of 500 entries. They can be difficult to delete (except all at once), so be careful with your experiments!
3. Add a speed (or proximity) alert to your Custom POIs. These are treated differently, and again, appear 'sooner'. If you don't actually want to be alerted, a 124mph Speed Alert is a good setting. This is the maximum value allowed.

Please clarify. What do you mean by height? Are you talking about the distance at which your GPSr will sound an alert? If so, you can set that by using the POI Loader provided by Garmin. Let us know what you mean by "height."

oh, sorry. i just meant "zoomed out" so i can see more of the full map instead of a more detailed area.

Drat - I'll have to find another question for my answer

FWIW I think that was (will be) a great answer... once you find the question. (chuckle)