I’m not sure if I should post here, a different thread, or start a new thread. If this is the wrong place, please move it or let me know and I will. 
For writing, I currently use nvUltra (still in beta) and MultiMarkdown Composer. Currently, the transclusion syntax is {{…/folder/file.md}}.
I’m less concerned with the syntax itself (happy with square brackets or curly braces…or something new). But it seems that the current syntax does not allow me to link to .md files in other directories (nvUltra and MC do).
Am I doing something wrong (there are spaces in the folder names so perhaps I need to add %20)?
I keep my zettelkasten in the root directory, and then have:
…/08 Reference/definitions/
…/08 Reference/wordstudies/
I would love to transclude various definition or wordstudy files into my zettelkasten notes as I write.
I’m probably doing something wrong, but…. 
Thank for any insight!