Collocations in the sense of idiosyncratic lexical co-occurrences are one of the main barriers and challenges for any second language (L2) learner. In Computer Assisted Language Learning (CALL), a number of works deal with the automatic recognition of collocation errors and compilation of candidate lists for their correction. However, this is not sufficient. Firstly, to obtain a clear picture of the difficulties experienced by learners in order to be able to offer targeted aid to learners, a fine-grained linguistic analysis of collocation errors and their annotation in learner corpora is necessary. Secondly, programs must be developed that make concrete correction suggestions, besides providing correction candidate lists, and supply a learner with illustration and didactic material that is oriented towards the types of collocations with which this learner has difficulties. In our work, we attempt to push the state-of-the-art one step further in both of these strands of research, focusing on Spanish as L2. Within the first strand, we carry out a detailed collocation-oriented annotation of a fragment of the corpus of learners of Spanish CEDEL2. Within the second strand, we experiment with a number of strategies for choosing the most likely correction of a collocation error.