I don't usually solo (although I did get to around Round 45 to get Big Baller, yes it was with Wunderwaffe running around in circles haha), so this is what I generally do for Der Riese. I usually find this works well for me and the group. It could be seen as a suggestion, but really I'm just letting you all know what I do in a very brief and general way.

To start out, I get a knife kill in that window near the door to the right of someone facing directly in front and looking at the PaP machine, next to the unlockable door that people usually go for first (if that made sense). Then, I immediately unlock that door. Depending on how proactive people are, I'll usually continue to get knife/pistol kills until I get to the box and turn on the power. All my efforts usually focus on unlocking doors. Once we turn on the power, I'll indulge and get myself a Gewehr. I'll continue to get knife/rifle kills until I have enough to unlock the door behind the box that contains the Bowie and the popular balcony camping area. I'll then link that teleporter, and save my points until I buy a Bowie.

Depending on my mood, I'll probably keep the Bowie for a while and just continue to focus my energies on unlocking the next teleporters. There's really no need for me to try for the box until later when all the busy work is done. A lot of my strategy depends on how proactive and willing my teammates are in helping out, but generally I put all my faith in myself and in my efforts to move our team along (I'll also go for Juggernog rather early as well because of this reason). When I have the teleporters done and am confident enough, I'll try for the box. When I get a weapon I like (by this time my team's probably at the camping balcony) I'll probably restrict myself in saving for Speed Cola first, and PaP second.

The rest is a little open-ended. I generally try to get things done and try to be as proactive as I can. I previously went for Trenchgun and Juggernog, but when I started to seriously consider my strategy I abandoned this rather quickly: You get little points for it and my efforts, provided I had the skill to not get myself cornered, could be spend in maximizing the amount of points I receive.

Hope that helped give you guys a feel on where I stand, Zombie-wise.

nice,

usually when i play i go where ever my teamates arent so i can get most of the points. usually i go get a thompson and camp in that room while everone else is at the box. that way i get the points and i get jugg and speed earlier that everyone else, then just spend my money on teleporters and pap my weaponds