Got this error in a 5 man party, i assume is caused by a druid.
target health bar was not working properly, (showed the good amount of hp left but was still full) same with player bar
I created an account to submit this error. don't know if i will help.

Thank you for the great job you pull up on these addon

Message: ...bs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1298: attempt to perform arithmetic on local 'castTime' (a string value)
Time: Fri Oct 18 22:35:09 2019
Count: 19
Stack: ...bs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1298: attempt to perform arithmetic on local 'castTime' (a string value)
...bs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1298: in function <...bs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1289>
...bs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1484: in function `?'
...bs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:2091: in function <...bs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:2090>

Locals: casterGUID = "Player-4475-0199EAD3"
spellID = 5187
amount = 244
castTime = ""
unit = "party4"
endTime = nil
(*temporary) = 42413.907000
(*temporary) = 42413.907000
(*temporary) = 1
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = "attempt to perform arithmetic on local 'castTime' (a string value)"
guidToUnit =

{
Player-4475-01EB1D51 = "party1"
Player-4475-01210FE3 = "party3"
Player-4475-0199EAD3 = "party4"
Player-4475-01E02D84 = "party2"
}
pendingHeals = {
}
DIRECT_HEALS = 1
loadHealList = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1264
HealComm = {
TargetLastTarget = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1818
decompressGUID = {
}
bucketFrame = {
}
TargetLastFriend = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1814
compressGUID = {
}
UNIT_SPELLCAST_CHANNEL_START = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1677
GetNextHealAmount = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:333
bucketHeals = {
}
UseAction = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1823
itemSetsData = {
}
currentModifiers = {
}
aurasUpdated = true
GetCasterHealAmount = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:468
CASTED_HEALS = 3
UNIT_SPELLCAST_CHANNEL_UPDATE = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1736
callbacks = {
}
removeRecordList = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:163
getRecord = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:126
UNIT_SPELLCAST_DELAYED = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1736
Target = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1780
GetOthersHealAmount = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:452
UNIT_AURA = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1183
tempPlayerList = {
}
GetPlayerHealingMod = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:305
UPDATE_MOUSEOVER_UNIT = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1758
ZONE_CHANGED_NEW_AREA = defined @interface\AddOns\LunaUnitFrames\libs\LibClassicHealComm-1.0\LibClassicHealComm-1.0.lua:1169
healingModifiers = {
}
hotMonitor = {
}
spellData = {
}
guidToUnit = {
}
CHARACTER_POINTS_CHANGED = defined @interface\Ad