I took about 1 hour & 30 minutes to finish this campaign. I found no bugs, & bot navigation went well. Supplies were enough as well. In this campaign, every map has at least 2 tank challenges. The hints, directions & highlights are quite clear, but some locations need clearer hints (I'll list the locations that might confuse players for awhile). However, during my play, I removed "tankvariant" in the mission script because I loved L4D2 tank & I usually used spider venom custom skin for that. Normally, all tanks in the campaign are L4D1 tanks from map 1 to finale. There are many alarm/ running events, & this campaign is somehow more difficult than normal campaign due to more frequent horde & special infected spawns. I forgot how many special infected I had killed on every map, but I think it's still less frequent than the Hard Eight mutation. Probably some horde spawns are bugged (or they're just there to add more challenges?). I'll list some possibly bugged horde locations below . Map 1 - It has a long cutscene that causes some zombies & special infected are standing by outside the saferoom before the survivors are ready. A spitter could be dangerous if she spits acid during the cutscene. Probably it would be better if the special infected spawn is not active until survivors get out of the saferoom. - There's a long panic event after facing the first tank in a post. In my case, the horde kept coming when I was defending outside after tank's death while looking for a path, & stopped after I got out of the building. . Map 2 has no problem. . Map 3 - It has a problem in earthquake event, because a tank also comes along with the special infected & endless horde, & the horde will only stop after the alarm is turned off. - The alarm switch during earthquake event has a highlight, but the problem is, the switch is out of sight & quite far so the highlight is small & can be missed during the distracted focus when dealing with endless horde. I took several detours around the area just to figure out where the switch was. If it's possible, it would be better to put some instructions or pointing arrow near the switch so that the distracted players can still see in a glance when looking around. - Near the end of map 3, I found something strange. A gang of 3 smokers came together at once to greet me at a corridor of certain building. . Map 4 is fine, but beware of the watery cave. The water is quite high so a crouching hunter & a jockey get their hide-and-seek playground. . Map 5 has a random path generator leading to a place to turn on power in order to open a rolling door. I played twice, & the paths were different. & there's alarm event after opening the rolling door. . Map 6 has a tricky path, just like the original. Because I forgot the path for a moment, I was stuck for few minutes to find out the way. & the challenging part is the battle at the elevator. I restarted once because a charger suddenly charged me out of elevator after jumping down to the elevator. . And the finale is wide & explorable. I still remembered the tricky path so I could go to where the radio was in no time. There are some good spots to camp. But somehow, the special infected & horde sometimes still come even before turning on the radio, just right when survivors are going up to 2nd floor. Other than that, there's no problem & bots can enter the helicopter smoothly. . In short, this extended version has more challenges on every map. The horde & special infected spawns are somehow more frequent, so, melee weapons can be the best friends here. It's a good campaign to vary the play between the original & this extended version. I'll keep this to play again later.