1) like I wrote I know how to set original preferences (default by Photoshop), it's not problem. But what if a user change colours of Photoshop Layers Transparency, and then this person run my script? If I use that script you provided then it will change settings to default, not an user set meantime. And here's problem because I don't see anything what could be used as well known pre = preferences.rulerUnits at beginning of script, then chagne it meantime, and retrieve at end by preferences.rulerUnits = pre. After all it's not bad to restore transpareny colours to default, but that's not the point. Anyway I did so untill someone come with proper solution.
2) It's not possible to change "linear" string to "Lnr " character, because there is no stringIDToTypeID('linear') but only 'linear', and to be precise its (in extract from my code): (dsc6 = new ActionDescriptor()).putString(sTT('name'), 'Linear'). If there is some way to do something more than for example for english or polish versions: (dsc6 = new ActionDescriptor()).putString(sTT('name'), 'Lin' + locale == 'pl_PL' ? 'iowy' :'ear')) I'll be happy to get to know it! For now I changed code a little, that for non-englsih versions there won't be drop shadow effect, but an information at beggining to check it and then change it. I could myself check all languages versions but that's worst I could do

however it'd solve the problem. It's the same with verstion of Photoshop. In CS2 it can't be run fully because there was bug with checking bounds of selection etc Ah btw, originally I wanted to use this value (1282306592), but again there is plain text not text taken to stringIDToTypeID.
3) I made information about pressing f kay to change screen mode like you suggested. But I think if some users visit (Photoshop <-- not only) Scripting forums they already know it
How to turn off creating and writing ScriptListenerJS.log any time I want in CS5.1 ? How to use Clean Listener in Action Events Manager, becaue I didn't see what it does after adding to Events and reopening Photoshop :/