I'm forwarding a discussion from the luaotfload issue tracker as it is possible that it indicates a bug introduced between version 1.0.0 and 1.0.4
In the following document the ^^^^0645 is displaced to the left. With luatex 1.0.0. (miktex) only if it is used in a \hbox. With luatex 1.0.4. in all three cases. The luaotfload version was the same, as fontloader I used the newest from the context minimals. So it looks as if some change in the engine was made -- perhaps to correct the \hbox error -- which made the problem worse. Some more details and some pictures can be found here: https://github.com/lualatex/luaotfload/issues/410 Disclaimer: I can't read or write arabic or some other right-to-left-script. \documentclass{article} \begin{document} \textdir TRT \font\amiri={file:amiri-regular.ttf:script=arab} at 80pt \amiri ^^^^0637 ^^^^0645^^^^062d^^^^064a^^^^0637\par \leavevmode\hbox dir TRT {^^^^0637 ^^^^0645^^^^062d^^^^064a^^^^0637} \vbox dir TRT {^^^^0637 ^^^^0645^^^^062d^^^^064a^^^^0637} \end{document} -- Ulrike Fischer http://www.troubleshooting-tex.de/
