UDM_PARAM_STOPFILE - Defines name and path to stopwords file. (There is a small difference with mnoGoSearch - while in mnoGoSearch if relative path or no path entered, it looks for this file in relation to UDM_CONF_DIR, the module looks for the file in relation to current path, i.e. to the path where the php script is executed.)
UDM_PARAM_WEIGHT_FACTOR - represents weight factors for specific document parts. Currently body, title, keywords, description, url are supported. To activate this feature please use degrees of 2 in *Weight commands of the indexer.conf. Let's imagine that we have these weights: