[NTG-context] Best way to prevent wrong column/page break with par starting with \starthanging

Dear all, I am using \starthanging to implement dropcaps (with small pdf files). I use this Inside mixedcolumns (2 columns). I’d like to know if there is a better way than \testcolumn[N], N being the number of lines of the dropcap, to prevent the location of dropcap being cut between end of column/page and beginning of next. Tried \keeplinestogether{N} instead but it does not work in all cases. That question was mainly to see if there were any possibility to avoid some blank lines at end of some columns (ie not balanced in given page). Thanks a lot Best regards Joseph