Hi,
I have the same problem about the floor with 2 stages... 
When a character moves left or right to make the screen scroll, the second character who is still standing move and come sliding across the floor to the opposite direction.
Here the code for these stages :
Spoiler, click to toggle visibilty
[Info]
name = "Baxter Launchpad"
;by SLotman 2005
[Camera]
startx = 0
starty = 0
boundleft = -100
boundright = 1200
boundhigh = -300
boundlow = 400
verticalfollow = .4
tension = 50
[PlayerInfo]
p1startx = -70
p1starty = 0
p1startz = 0
p1facing = 1
p2startx = 70
p2starty = 0
p2startz = 0
p2facing = -1
leftbound = -328
rightbound = 1400
topbound = 0
botbound = 0
[Scaling]
topz = 0
botz = 50
topscale = 1
botscale = 1
[Bound]
screenleft = 0
screenright = 0
[StageInfo]
zoffset = 205
autoturn = 1
resetBG = 1
[Shadow]
color = 100,100,256
yscale = 0.41
reflect = 0
[Music]
bgmusic = sound/ff.mp3
bgvolume = 255
bgm.loop=1
end.time=999999999
[BGdef]
spr = stages/baxter2.sff
debugbg = 0
[BG background]
type = normal
spriteno = 0,1
mask = 0
start = -180, -220
tile = 1,0
delta = 0.16, 0.8
velocity = -0.2, 0
[BG back buildings]
type = normal
spriteno = 0,2
mask = 1
start = -190, -180
delta = 0.14, 1
[BG buildings]
type = normal
spriteno = 0,3
mask = 1
start = -180, -180
delta = 0.16, 1
[BG floor]
type = normal
spriteno = 0,4
mask = 1
start = -200, -250
delta = 0.2, 1.1
Spoiler, click to toggle visibilty
[Info]
name = "Ray Palmer's Lab"
;by Marvelvsdcu 2010
[Camera]
startx = 0
starty = 0
boundleft = -898
boundright = 1800
boundhigh = -45
boundlow = 0
verticalfollow = 0.3
tension = 50
[PlayerInfo]
p1startx = -70
p1starty = 0
p1startz = 0
p1facing = 1
p2startx = 70
p2starty = 0
p2startz = 0
p2facing = -1
leftbound = -1039
rightbound = 1550
topbound = 0
botbound = 0
[Scaling]
topz = 0
botz = 50
topscale = 1
botscale = 1.2
[Bound]
screenleft = 15
screenright = 15
[StageInfo]
zoffset = 210
autoturn = 1
resetBG = 0
[Shadow]
intensity = 90
color = 100,100,100
yscale = 0.35
reflect = 0
[Music]
bgmusic = sound/atom.mp3
bgvolume = 255
bgm.loop=1
end.time=999999999
[BGdef]
spr = stages/atomlab.sff
debugbg = 0
[BG background]
type = normal
spriteno = 1,0
mask = 0
start = 150, -70
delta = 0.16, 0.8
[BG lightning]
type = anim
actionno = 1
mask = 1
start = 225, -90
delta = 0.16, .8
[Begin Action 1]
3,5, 0,30, 1
3,4, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,4, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
3,5, 0,30, 1
3,4, 0,30, 1
Loopstart
3,0, -30,20, 1
3,2, 0,0, 1
3,1, 0,0, 1
3,3, 0,0, 1
3,1,0,0,1
3,2,0,0,1
3,0,-30,20,1
[BG comp ceiling]
type = normal
spriteno = 1,1
mask = 1
start = 145, -70
delta = 0.16, .8
[BG trans]
type = normal
spriteno = 2,0
mask = 1
start = 225, -90
delta = 0.16, .8
trans = add
[BG lab equipment]
type = normal
spriteno = 1,3
mask = 1
start = 225, -90
delta = 0.16, .8
[BG monitors]
type = normal
spriteno = 1,5
mask = 1
start = 145, -35
delta = 0.2, 1.1
[BG desk]
type = normal
spriteno = 1,2
mask = 1
layerno=0
start = 110, -95
delta = 0.2, 1.1
[BG lamp]
type = normal
spriteno = 1,4
mask = 1
layerno=1
start = 150, -70
delta = 0.2, 1.1
trans = none
I'm desperate could someone help me please ? (I'm start to become crazy about this 
)
