This error.log entry seems to be related to smuggling:
It goes together with this compile.log entry:
Possibly related to the escape from the coastguard.
This is from @Hylie Pistof's smuggling logs world map.7z posted at Fix in Progress - Smuggling: Chance to be Caught is either 0% or 100% | PiratesAhoy!
This is a funny one because:
I think I figured it out though and it appears to be my fault.
The "Rand_ContrabandInterruptionAtSeaEnded" function calls this function BEFORE it gets to that next line:
So my "Just in case" line there should probably be removed.... 
Code:
RUNTIME ERROR - file: quests\quests_check.c; line: 436
missed attribute: win_condition
RUNTIME ERROR - file: quests\quests_check.c; line: 436
no rAP data
It goes together with this compile.log entry:
Code:
Quest name error FOUND in CommonQuestComplete
This is from @Hylie Pistof's smuggling logs world map.7z posted at Fix in Progress - Smuggling: Chance to be Caught is either 0% or 100% | PiratesAhoy!
This is a funny one because:
Code:
void OnQuestComplete(aref quest)
{
if(!CheckAttribute(quest,"over") && CheckAttribute(quest,"win_condition"))
{
if(quest.win_condition == "_") return;
quest.over = "yes";
// PB: Error checking -->
ref PChar = GetMainCharacter();
DeleteAttribute(PChar, "questnotfound"); // Make sure this is GONE!
// EXTRA CHECK -->
if (!CheckAttribute(quest, "win_condition"))
{
TraceAndLog("QUEST ERROR: Please post your compile.log file at piratesahoy.net!");
DumpAttributes(quest);
}
// EXTRA CHECK <--
// Common Quests
CommonQuestComplete(quest.win_condition); // <-- Execute the actual quest case
if(!CheckAttribute(PChar, "questnotfound"))
{
trace("Quest name " + quest.win_condition + " FOUND in CommonQuestComplete"); // <------------ IT ERRORS OUT ON THIS LINE ------------
return;
}
DeleteAttribute(PChar, "questnotfound");
The "Rand_ContrabandInterruptionAtSeaEnded" function calls this function BEFORE it gets to that next line:
Code:
void StopCoastalGuardPursuit()
{
ref Pchar, rCap1, rCap2, rCap3;
Pchar = GetMainCharacter();
rCap1 = CharacterFromID("Coastal_Captain01");
rCap2 = CharacterFromID("Coastal_Captain02");
rCap3 = CharacterFromID("Coastal_Captain03");
group_DeleteGroup("Coastal_Guards");
ChangeCharacterAddressGroup(CharacterFromID("Coastal_Captain01"), "None", "", "");
ChangeCharacterAddressGroup(CharacterFromID("Coastal_Captain02"), "None", "", "");
ChangeCharacterAddressGroup(CharacterFromID("Coastal_Captain03"), "None", "", "");
DeleteAttribute(Pchar, "quest.Rand_ContrabandInterruptionAtSeaEnded"); // PB: Just in case
}
