@tpartner : just to confirm : 2.5X have same issue ?

@DenisChenu, yes, it was tested with 2.55.

@DenisChenu, $slider_default is null in quanda_helper.php ~ line 2931.

OK, i already do some fix in 3.0 and have another fix to do : https://bugs.limesurvey.org/view.php?id=11732

@tpartner : something i don't understand :
in 2.55 : middele value or initial value seems OK :
in 2.55 : "When using 0 as a minimum, the slider is initially loaded set to the maximum value even if "Slider initial value" is set to 0" : can not reproduce : http://testing.sondages.pro/masterall/index.php/867188
masterall is actually (today) Version 2.55.1

Else in 2.55 or 3.0 : 0 is not set at value when use Slider initial value = 0 . But more is not set even if 'move to 0 (see 0) and go next : http://testing.sondages.pro/answershtml/index.php/867188/lang/en/newtest/Y

@DenisChenu, I just pulled 2.55.2 and all sliders in my test survey still initialize at the max value (5), not in the middle or at 0 as the settings indicate. Tested in FF, Chrome and IE 11.

... still can not reproduce .... (i just reset/pull)

BUT : i don't fix it in 2.5X : all js is inlined. I rework it for 3.X , then fixing it only in 3.0 (sorry).

It's not just me - https://www.limesurvey.org/forum/can-i-do-this-with-limesurvey/107494-allocate-weighting-across-subquestions-ranking-with-percentage#144054

I didn't say that :). I just say i don't understand why you have this issue and not me.

For 3.0 : Sorry : but i work hard to move inline JS to one external function to better fixing it. It's one of the reason why i take time to work on 3.0 (and don't publish any plugin, take less time on my project) since one month. Then : i didn't fix it in 2.55. Someone else can do it.

Fix committed to develop branch: http://bugs.limesurvey.org/plugin.php?page=Source/view&id=21392

Version 3.0.0-beta.1 released