Found a small bug while installing limesurvey206plus-build151018 on my local system.

OS: Ubuntu 14.04
Http Server: Apache/2.4.7
Database: MySQL 5.5.38
PHP: PHP 5.5.9

Installation Directory: /home/vishal/data/web/ls206p

Issue: Can not install as get error on home page, after extracting souce zip and granting read/write permission to installation directory.

"Internal Server Error

opendir(/var/www/html/web/ls206p/tmp/assets/c159e1ca): failed to open dir: No such file or directory"

Reason: Installation directory is configured using apache directory alias(/etc/apache2/sites-available/000-default.conf). And ExtendedClientScript.php has code that uses "DOCUMENT_ROOT" to find the root path. With directoty alias its returning incorrect physical path as expected, and that crashes the installation with above error.

Solution Applied:
File: application/extensions/ExtendedClientScript/ExtendedClientScript.php

Line 205

Original Code
$this->basePath or $this->basePath = realpath($_SERVER['DOCUMENT_ROOT']);

Changed to:
$this->basePath or $this->basePath = rtrim(dirname(realpath($_SERVER['CONTEXT_DOCUMENT_ROOT'])),'\/');

This solution only applied so I can continue setup on my local system. Its not tested on any other other platform.