I recently downloaded and updated to OOO BETA and upon playing I have noticed that all the map markers/icons are gone. The only remaining ones are The imperial City districts and the Prison Sewerx Exit.

What file/folder controlls this and how can I get them all back?

http://devnull.sweetdanger.net/OOO/OOO_134_readme.pdf

Page 15, but read some of the rest of it too,

I attempted to read the Readme as soon as I downloaded the mod but here's what it contains.

Tens of hundreds of pages or this:

$??n?@2 #?ìè?7"!
Yx?F$D?7nD?Yx?F$?ù7bVK$s?].!?C ?ì??7"?
?x?F$°?7n?J

Your PDF reader is broken.

Get Foxit Reader or Adobe Reader and make sure you have the browser extension installed.

Or, if you have one installed already, just right click the link I posted and choose "save link as" and make sure it's in PDF format...ie the extension remains .pdf

Basically, you have to discover the city locations (except Imp City) to get their map markers. Personally, I like the feature a lot. If you don't, OOO comes with a OOO-Map_Markers_Stock.esp which removes the feature.