I've downloaded a notebook from develop.wolframcloud.com and opened it in 10.3.1 (running on Win 10). When I evaluate some cells I get syntax errors along the lines of...
Syntax::sntxf: "\"Clear[\" cannot be followed by \"riskVariance"
And certain characters are highlighted in yellow, most often parentheses () or square brackets  and commas but sometimes larger items, say a whole function LHS. I wonder if this is caused by some weird font incompatibility.
Additionally all the cells that I have created are on inspection in StandardForm and attempts to convert them to InputForm does not seem to achieve anything, they stay resolutely in InputForm.