Hello everyone - I have been struggling for the last several days trying to figure out how to build and use my own symbols. I need a symbol for two kinds of formations - Stalactiflats and Stalagmaflats. These are basically stalagmites which are fat (several feet diameter) and flat on top like a table (or flat on the bottom). It appears there are two problems to solve. The first, which I address in this question, is how to get xTherion to use a custom symbol. The second is to figure out how to draw the symbol in Metapost. For now I am ignoring the second problem. One step at a time! After spending several hours going through Therion By Example, I was able to get a custom symbol to work, but only by replacing an existing symbol. I used the NSS "gradient point" example. Changing the Metapost code as shown does not produce any error messages. However, it also does not produce a symbol in the PDF output. All I get is a red dot. =============== code metapost def p_stalagmaflat_AMER (expr pos,theta,sc,al) = U:=(.15u, .4u); T:=identity aligned al rotated theta scaled sc shifted pos; pickup PenC; #Left Hand side thdraw (-.3u, -.2u) -- (-.7u, .1u); thdraw (-.2u, -.1u) -- (-.4u, .6u); #Centerline thdraw (0u, 0u) -- (0u, .9u); #Right side thdraw (.3u, -.2u) -- (.7u, .1u); thdraw (.2u, -.1u) -- (.4u, .6u); enddef; initsymbol ("p_stalagmaflat_AMER"); endcode ================== Since I am not replacing an existing symbol, I leave out the "symbol-assign" line. In xTherion I try to use this by inserting a point of type "u" and adding an option "-subtype stalagmaflat". I think this is where I am missing something ... How to call the custom symbol with a "u" point. Is this the right syntax? In the worst case I suppose I could set it up to replace a symbol that I won't use for this cave - a ladder, for example. That would probably cause quite a bit of confusion down the road, so I would much prefer to avoid it. I am using Therion 5.3.13 on 64-bit Fedora 20. Thanks - Bill Gee