These are the static meshes, textures and maps needed for a minimal installation of 1.9b (only DB-Cube and DB-Smallcube):
Maps
-------------------------------
DB-Cube.ut2
DB-Smallcube.ut2
Entry.ut2
entry_deathball.ut2
-------------------------------
Static Meshes
-------------------------------
E_Pickups.usx
ParticleMeshes.usx
WeaponStaticMesh.usx
XGame_StaticMeshes.usx
-------------------------------
Needed for maps:
-------------------------------
HumanoidHardware.usx
DB-Statics.usx
-------------------------------
Textures
-------------------------------
AbaddonArchitecture.utx
AbaddonArchitecture-epic.utx
AbaddonHardwareBrush.utx
AbaddonTerrain.utx
AlleriaArchitecture.utx
AlleriaTerrain.utx
ArboreaArchitecture.utx
ArboreaTerrain.utx
AWGlobal.utx
BloodFX.utx
CP_effects1.utx
Crosshairs.utx
CubeMaps.utx
DanFX.utx
DBMenu.utx
DeathballGFX.utx
DefaultFluid.utx
DeRez.utx
Dom-goose.utx
Egypt_tech_Epic.utx
EmitterTextures.utx
EpicParticles.utx
ExitScreen.utx
FireEngine.utx
H_E_L_Ltx.utx
HumanoidArchitecture2.utx
HumanoidArchitecture.utx
HumanoidHardwareBrush.utx
InstagibEffects.utx
InterfaceContent.utx
intro_characters.utx
LadderShots.utx
LastManStanding.utx
MenuEffects.utx
MikeDemoLevel.utx
Phobos2_cp.utx
PickupSkins.utx
Pipe_Set.utx
PlayerSkins.utx
SC_Volcano_T.utx
ServerIcons.utx
Shiptech.utx
SingePlayerThumbs.utx
skyline-epic.utx
SkyRenders.utx
TeamSymbols.utx
TeamSymbols_UT2003.utx
TowerTerrain.utx
UCGeneric.utx
UT2003Fonts.utx
WeaponSkins.utx
XEffectMat.utx
XGameShaders.utx
xGameShadersB.utx
XGameTextures.utx
-------------------------------
Needed for maps:
-------------------------------
HumanoidArchitecture.utx
HumanoidArchitecture2.utx
skyline-epic.utx
-------------------------------
I'm not sure how many ppl will still be needing this, but I figured since I had found it out myself, why not take 2 minutes and post it?
This set-up works for me
please tell me if something's wrong with it 
ps: I tested it by putting respectively either all .usx, or all .utx (or all .ut2 for the entry maps) in a different folder, starting through the deathball shortcut (!) and systematically putting the packages I needed back in the original folder.
Tested online, with bots and with all texture detail settings on and off (yes, I'm a noob) etc.
edit: I did have some problems getting into some servers, and I had to download/cache some seemingly basic packages
These are just the ones needed to run deathball, the rest is supposedly the server's mistake ^^; feel free to add the packages needed for your server
