What steps will reproduce the problem?
1. Download and install Raid Tracker and Badkitty
2. Load WoW
3. View Error

What is the expected output? What do you see instead?
All functionality ceases when this addon is run with the addon "RaidTracker"

What version of the product are you using?
BadKitty 1.5

Do you have an error log of what happened?
Date: 2009-02-04 19:19:57
ID: 1
Error occured in: Global
Count: 640
Message: ..\AddOns\BadKitty\BadKitty.lua line 496:
   attempt to perform arithmetic on field '?' (a nil value)
Debug:
   [C]: ?
   BadKitty\BadKitty.lua:496 BadKitty_UpdateMe()
   [string "*:OnUpdate"]:1:
      [string "*:OnUpdate"]:1
AddOns:
  Swatter, v3.1.11 (<%codename%>)
  WowheadLooter, v30018
  ACP, v3.0.10.15
  Align, v
  Atlas, v1.13.0
  AtlasBattlegrounds, v1.13.0
  AtlasDungeonLocs, v1.13.0
  AtlasOutdoorRaids, v1.13.0
  AtlasTransportation, v1.13.0
  AtlasLoot, vv5.03.02
  AtlasLootFu, vv5.03.02
  AutoBar, vv3.00.08.17 beta
  AutoProfitX, v2.04
  Babylonian, v5.1.DEV.130
  BadKitty, v
  Bagnon, v1.6.10
  BagnonForever, v1.1.1
  Bartender4, v4.2.5
  BeanCounter, v5.2.4013 (DingoII)
  BigBrother, v
  BuffEnough, v
  Cauldron, v0.9.9.55
  Chinchilla, v
  Chronos, v2.12
  Configator, v5.1.DEV.130
  CraftList2, v3.0
  CTExpenseHistory, v3.001 (CTMod 3.0)
  CTMailMod, v3.002 (CTMod 3.0)
  DBMCore, v
  DebugLib, v5.1.DEV.130
  Decursive, v2.4_beta_2_STABLE-1-g2500efb
  DrDamage, v1.6.0b
  ElkBuffBars, v2.2.3-148
  Enchantrix, v5.2.4013 (DingoII)
  EnchantrixBarker, v5.2.4013 (DingoII)
  EnhTooltip, v5.1.3715 (SnaggleTooth)
  FuBar, v
  FuBarBagFu, vv1.1.3
  FuBarDigiCamFu, vv1.1-1-gfb3b919
  FuBarDurabilityFu, v2.11
  FuBarExperienceFu, v1.1 $Revision: 65606 $
  FuBarGroupFu, v1
  FuBarGuildFu, v2.4.1-98
  FuBarLocationFu, v3.0
  FuBarLogFu2, v1.1.302-1.1.302-Release
  FuBarMoneyFu, vv1.2-1-g3618150
  FuBarNameToggleFu, vv1.2-1-g682f329
  FuBarPerformanceFu, v2.0.0
  FuBarSkillsPlusFu, v3.0.5
  FuBarTopScoreFu, vv1.0.2
  Gatherer, v3.1.11
  Geist, v30000.4
  Grid, v1.30000.2009011501
  GridManaBars, v0.88
  GridStatusHealingReduced, v3.0.3.23
  GuildCheck, v
  Informant, v5.2.4013 (DingoII)
  MalygosHelper, v$Revision: 2 $
  Mapster, v1.1.2
  Omen, v3.0.6
  OmniCC, v2.2.5
  oRA2, v2.0.$Revision: 628 $
  oRA2Optional, v2.0
  oRA2Participant, v2.0
  OutfitDisplayFrame, v0.5.9
  Outfitter, v4.4b4
  PallyPower, vv3.0.17-release
  Parrot, vv1.6.3.2
  PitBull, vr1878
  PitBullAura, v2.0
  PitBullBanzai, v1.0
  PitBullBarFader, v0.1
  PitBullCastBar, v2.0
  PitBullCombatFader, v0.1
  PitBullCombatIcon, v2.0
  PitBullCombatText, v2.0
  PitBullComboPoints, v2.0
  PitBullDruidManaBar, v2.0
  PitBullExperienceBar, v2.0
  PitBullHealthBar, v2.0
  PitBullHideBlizzard, v2.0
  PitBullHighlight, v2.0
  PitBullLeaderIcon, v2.0
  PitBullMasterLooterIcon, v2.0
  PitBullPortrait, v2.0
  PitBullPowerBar, v2.0
  PitBullPvPIcon, v2.0
  PitBullRaidTargetIcon, v2.0
  PitBullRangeCheck, v0.2
  PitBullReadyCheckIcon, v2.0
  PitBullReputationBar, v2.0
  PitBullRestIcon, v2.0
  PitBullSpark, v2.0
  PitBullThreatBar, v2.0
  PitBullVisualHeal, v2.0
  PitBullVoiceIcon, v2.0
  Prat30, vr215
  Prat30Libraries, v
  Quartz, v1.0
  QuartzFlight, v1.0
  QuartzFocus, v1.0
  QuartzGCD, v1.0
  QuartzInterrupt, v1.0
  QuartzLatency, v1.0
  QuartzMirror, v1.0
  QuartzPet, v1.0
  QuartzPlayer, v1.0
  QuartzRange, v1.0
  QuartzSwing, v1.0
  QuartzTarget, v1.0
  QuartzTimer, v1.0
  QuartzTradeskill, v1.0
  QuestLogCollapse, v
  RaidTracker, v2.2.18
  RatingBuster, v
  RBM2, v
  RBM2DeBuffWatch, v1
  Recount, v
  RogueFocus, v1.2.1
  SharedMedia, v3.0
  SimpleRaidTargetIcons, v1.08
  SlideBar, v3.1.11 (<%codename%>)
  Sort, v1.0
  Stubby, v5.2.4013 (DingoII)
  Talented, v1.9.4
  TipTac, v08.12.05
  TipTacItemRef, v08.12.03
  TipTacTalents, v08.11.05
  Torta, v0.1
  TotemTimers, v9.1 Beta3
  TrinketMenu, v
  VisualHeal, v
  XLoot, v0.9
  XLootGroup, v0.5
  XLootMaster, v0.7
  XLootMonitor, v0.7
  (ck=ccd)

Please provide any additional information below.
I know this above error lists a lot of addons so here's one with just Swatter, ACP, Badkitty and RaidTracker:

Date: 2009-02-04 19:29:43
ID: 1
Error occured in: Global
Count: 370
Message: ..\AddOns\BadKitty\BadKitty.lua line 496:
   attempt to perform arithmetic on field '?' (a nil value)
Debug:
   [C]: ?
   BadKitty\BadKitty.lua:496 BadKitty_UpdateMe()
   [string "*:OnUpdate"]:1:
      [string "*:OnUpdate"]:1
AddOns:
  Swatter, v3.1.11 (<%codename%>)
  ACP, v3.0.10.15
  BadKitty, v
  RaidTracker, v2.2.18
  (ck=5a)